New MicroPython cross-compiler, and vastly improved ESP8266 port

This release adds the MicroPython cross-compiler that can generate .mpy
files (pre-compiled bytecode) which can be executed within any
MicroPython runtime/VM.  The ESP8266 port is also vastly improved thanks
to a hugely successful Kickstarter campaign.  This port now has an
alternative event loop implementation to allow proper Berkeley sockets
using lwIP built from source, and a greatly improved network module.
Many extension modules are now enabled (ujson, ubinascii, uctypes,
uhashlib, urandom, uheapq, ure, uzlib) and the machine module includes
Timer, Pin, PWM, ADC, I2C, SPI, and basic UART.  Bignums are supported,
along with 30-bit precision floating point, and normal error messages.
There is FatFS support and uos.dupterm.

Many other improvements and bug fixes have been made to the core and
other ports.  The basic test suite can now run within a 16k heap.  Inline
assembler functions now support 4 arguments.  The Unix port has the -i
option to start the REPL after a script is finished.  The stmhal port now
exposes the flash and SD card as proper objects with the block protocol.
There is support for generic STM32F439 boards, the NUCLEO-F411RE board,
and targets to deploy via ST-LINK and OpenOCD.

py core:
- mpprint: fix sign extension when printf'ing %u, %x and %X
- vm: fix popping of exception block in UNWIND_JUMP opcode
- objstr: for str.format, add nested/computed fields support
- objstr: for str.format, don't allocate on the heap for field name
- extend native type-sig to use 4 bits, so uint is separate to ptr
- mpz: complete implementation of mpz_{and,or,xor} for negative args
- mpz: add commented-out mpz_pow3_inpl function, to compute (x**y)%z
- viper: allow casting of Python integers to viper pointers
- viper: allow uint as index to load/store, and give better error msg
- objarray: implement "in" operator for bytearray
- mpstate.h: fs_user_mount is now standard, reusable uPy functionality
- asmx64: add helper macro for generating REX_[WRXB] bits from a reg64
- asmx64: support all 16 regs in reg to memory move instructions
- emitnative: add check that RHS of viper store is of integral type
- repl: check for an identifier char after the keyword
- vm: add macros to hook into various points in the VM
- parse: use m_renew_maybe to ensure that memory is shrunk in-place
- malloc: provide a proper malloc-based implementation of realloc_ext
- emitinlinethumb: use qstrs instead of char* for names of asm ops
- add MICROPY_DYNAMIC_COMPILER option to config compiler at runtime
- stackctrl: add mp_stack_set_top() to explicitly set stack top value
- emitglue: get persistent bytecode working on Linux ARM platform
- objboundmeth: allocate arg state on stack if heap alloc fails
- use MP_SMALL_INT_POSITIVE_MASK to check if uint fits in a small int
- fix passing of some wide int types to printf varg format list
- objarray: fix array slice assignment when array is reallocated
- formatfloat: fix buffer overflow when formatting tiny numbers
- objfun: allow inline-asm functions to be called with 4 arguments
- frozenmod: allow port to override lexer to use for frozen modules
- parse: don't allocate an extra parse node for power exponent
- parse: when looking up consts, check they exist before checking type
- stream: add mp_stream_writeall() helper function
- stream: fix object vs ptr usecase in mp_stream_writeall()
- modio: initial implementation of io.BufferedWriter class
- modio: implement io.BufferedWriter.flush()
- modio: io.BufferedWriter: describe flushing policy
- formatfloat: fix case of float format where leading digit was "10"
- formatfloat: fix further cases of buffer overflow in formatting
- parsenum: use pow function to apply exponent to decimal number
- ringbuf.h: add reusable ring buffer class
- map: prevent map resize failure from destroying map
- move stream-related declarations from obj.h to stream.h
- combine continuous block of emit steps into with_cleanup emit call
- implement basic with support in native emitter
- objarray: fix array.append so it doesn't extend if append fails
- stream: add bigger inventory of stream ioctl's
- stream: add Python-level ioctl() method

extmod:
- update uzlib to 1.2.2
- fsusermount: introduce separate mkfs() function
- fsusermount: implement separate umount() function
- fsusermount: change block protocol to support ioctl method
- modmachine: truncate integers that are to be stored using mem*
- fsusermount: expose umount as a public function
- fsusermount: support mounting of multiple block devices
- vfs_fat: object-oriented encapsulation of FatFs VFS
- vfs_fat_diskio: reusable FatFs module, move from stmhal/diskio
- vfs_fat_file: reusable FatFs module, move from stmhal/file
- vfs_fat_ffconf: reusable FatFs module, move from stmhal/ffconf
- vfs_fat: move listdir() method from stmhal for reuse
- vfs_fat: add .remove() method
- vfs_fat: add .mkdir() method
- vfs_fat: add fat_vfs_import_stat(), reusable import stat routine
- vfs_fat: add .rename() method
- vfs_fat: add lexer, move from stmhal port for reuse
- vfs_fat_lexer: make conditional on FatFs support enabled
- modlwip: add .print() method
- modlwip: implement dummy setsockopt()
- modlwip: add stream protocol read method
- modlwip: add dummy .makefile() method
- modlwip: add stream .read() and .readline() methods
- modlwip: check for state change during recv busy-wait loop
- modlwip: still process remaining incoming data of a closed socket
- modlwip: add .write() stream method
- modlwip: support non-blocking recv()
- modlwip: factor out "socket connected" check to a function
- modlwip: use MICROPY_EVENT_POLL_HOOK for event polling if defined
- modlwip: rework getaddrinfo() data passing
- modlwip: add socket.setblocking() method
- modlwip: lwip_tcp_receive: Properly map lwIP error to POSIX errno
- uctypes: use mp_binary_get_val helper when extracting value
- uctypes: finish support for FLOAT32 and FLOAT64 types
- modwebsocket: start module for WebSocket helper functions
- modwebsocket: implement read support
- modlwip: add SOL_SOCKET and SO_REUSEADDR constants for setsockopt()
- modlwip: implement setsocketopt(SO_REUSEADDR)
- modlwip: lwip_tcp_send: handle properly send buffer full condition
- modlwip: add lwip->POSIX error map for lwIP 1.4.0
- modlwip: lwip_socket_setsockopt: handle option value properly
- vfs_fat_diskio: actually support sectors != 512 with Python blockdevs
- modwebsocket: properly check number of args to constructor
- modure: re_exec() renamed to ure_exec() due to collison in 4.3BSD
- modwebsocket: make sure to propagate EOF
- modwebsocket: reset mask between packets
- modwebsocket: add option for blocking writes to non-blk sockets
- modwebsocket: record current fragment type (binary/text/etc.)
- modwebsocket: allow to get type of last read data using ioctl()
- modwebsocket: implement MP_STREAM_SET_DATA_OPTS ioctl
- modwebsocket: split websocket-related defines for reuse
- modlwip: fix for loss of data in unaccepted incoming sockets
- modwebsocket: support write size beyond 125 bytes

lib:
- fatfs: add support for sector sizes larger than 512 bytes
- axtls: update to the latest upstream master

drivers:
- sdcard: add support for multi-block read/write; add SD test

tests:
- open_plus: add tests for "r+", "w+" open modes
- pyb: add simple test for stm module on pyboard
- run-tests: add esp8266 target
- bytearray1: add testcases for "in" operator
- vfs_fat_ramdisk: add test for VfsFat
- vfs_fat_ramdisk: switch to ioctl-based blockdev API
- vfs_fat_ramdisk: allow to override sector size
- vfs_fat_ramdisk: skip test if can't allocate ramdisk
- skip uctypes and urandom tests not supported byt the WiPy
- vfs_fat_ramdisk: add .listdir() testcase
- vfs_fat_ramdisk: add testcase for .remove()
- vfs_fat_ramdisk: add testcase for .mkdir()
- vfs_fat_ramdisk: allow to run in native mode (don't use "with")
- vfs_fat_ramdisk: add testcase for .rename()
- reduce large object allocations so tests can run with small heap
- print_exception: use exception which prints the same regardless of config
- recursive_iternext.py: make low-heap friendly
- run-tests: simplify handling of newline in output from tests
- run-tests: add cmd line option "--heapsize"
- split large tests into smaller files, to run with a small heap
- add new subdir "stress/" specifically for stress tests
- add a test for argument passing to inline-asm functions
- add test for io.BufferedWriter
- wipy: add Timer class tests
- float2int_fp30: variant of float2int for 30-bit stuffed float
- string_format_fp30: variant of string_format for 30-bit stuffed float

mpy-cross:
- add new component, a cross compiler for MicroPython bytecode
- give a more sensible error message when file doesn't exist
- remove setting of MICROPY_FORCE_32BIT=1 from Makefile

unix port:
- file: stop assuming that O_RDWR == O_RDONLY | O_WRONLY
- enable VfsFat support
- enabled importing of persistent bytecode (.mpy files)
- modsocket: add comment regarding close() error checking (which is none)
- unix_mphal: hack to make uos.dupterm() actually work
- implement -i option (inspect - start REPL after script is finished)
- file: parse "buffering" argument of open() builtin
- file: "encoding" arg to open() isn't kw-only
- djgpp errno.h have no ENOTSUP, so define it to Linux value
- freedos: strip and size names for binaries

stmhal port:
- diskio: introduce MICROPY_HW_HAS_FLASH setting
- move stmhal-specific FatFs routines/structs to fatfs_port.c
- file: recast as "FatFs file" class, to support other VFS types
- file: for self-contained usecase, don't define global types
- improve NUCLEO-F401RE build, with UART2 as REPL
- expose flash and SD card as proper objects with block protocol
- add mount/umount/mkfs to os module
- add a function for setting the pin alternate function
- NUCLEO 401 - Add a bunch of missing pins and reorder the pins
- CERB40 - Add pins defines for I2C3
- NUCLEO 401 - Add definitions for I2C2 and I2C3
- diskio: add provision for default returns for ioctl INIT/SEC_SIZE
- improvements to the STM32F4DISC UART config settings
- enabled importing of persistent bytecode (.mpy files)
- make SPI use mp_hal_gpio_set_af
- switch from dfu-util to tools/pydfu.py for default deploy method
- add stmhal-specific README.md with extra details for this port
- add makefile target to deploy stmhal build via ST-LINK
- add support for generic STM32F439 board (non DISCO)
- add makefile target and configuration to deploy via OpenOCD
- add board definition files for NUCLEO_F411RE
- rename STM32F401NUCLEO to NUCLEO_F401RE
- NUCELO_F401RE cleanup
- consistently enable USB SOF Irqs for all USB modes (FS and HS)

qemu-arm port:
- reinitialise uPy heap and runtime at start of each test
- enable builtin override feature, and enable more tests

cc3200 port:
- add stmhal/builtin_open.c to build
- fix breakage after VfsFat refactor
- finally fix the Timer class API
- improve robustness of the I2C driver
- simplify the Timer API and correct the documents
- fix "debug" build
- improve robustness of WLAN during sleep modes
- rename 'server' class to 'Server' for consistency
- update WiPy software version to 1.2.0

esp8266 port:
- modesp: implement flash_write(), flash_erase()
- README: add hint about adding toolchain to PATH
- modpybrtc: simplify multiplication by fixed-point value
- switch bignum implementation from long-long to mpz
- enable float support, using 30-bit stuffed floats
- enable math module
- allow Makefile's PORT variable to be overridden
- change "soft reboot" message to work with pyboard.py
- add network.ifconfig()
- enable ujson, ubinascii, and uctypes modules
- esp8266.ld: link in SDK version section
- enable config settings helpful for debugging
- enable uhashlib module
- enable more features in mpconfigport.h
- add mp_hal_delay_us function
- add time.{sleep_ms,sleep_us,ticks_ms,ticks_us,ticks_diff}
- reset "virtual RTC" on power on
- modutime: support float argument to time.sleep()
- add modmachine with mem* arrays
- modmachine: basic implementation of Timer for OS virtual timers
- modmachine: changing params of a timer requires disarming it first
- etshal.h: add timer functions prototypes
- modmachine: use etshal.h
- modmachine: timer: Add ONE_SHOT and PERIODIC symbolic constants
- add custom _assert() function
- implement Pin.__call__() and Pin.OPEN_DRAIN mode
- expose simple pin API at C level
- modpybpin: add support for GPIO16
- modmachine: add Pin class from modpyb
- etshal.h: more prototypes of ESP8266 SDK/BootROM functions
- support raising KeyboardInterrupt on Ctrl+C
- uart: add uart_flush() function
- allow Makefile's BAUD variable to be overridden
- enable stack overflow checking
- don't gc-collect BSS
- enable modlwip
- Makefile: add define for ESP8266 lwIP
- put more code in iROM section
- main: module to run on boot is "boot", not "main"
- move pyb.freq to machine.freq
- modnetwork: allow to configure STA and AP interfaces separately
- move wifi_mode() and phy_mode() to network module
- modnetwork: add per-interface .active() method
- modnetwork: move config defines to the top
- modnetwork: introduce interface .config() method
- modnetwork: add symbolic names for network interfaces: STA_IF & AP_IF
- add alternative event loop implementation
- feed WDT in ets_loop_iter()
- ets_alt_task: be sure to "pop" event before calling its handler
- ets_alt_task: update for vendor SDK 1.5.0
- esp_mphal: add higher-level event polling function
- define MICROPY_EVENT_POLL_HOOK for the port
- switch to lwIP built from source
- store frozen modules in FlashROM
- ets_alt_task: make FIRST_PRIO=0 to cover all task priorities
- make mp_hal_delay_us work with new event framework
- enable urandom module
- add module weak link from json to ujson
- enable more extmod's: uheapq, ure, uzlib
- enable non-blocking stream support
- add "socket" and "usocket" aliases for lwip module
- enable auto-indent in REPL
- expose pin object as a public structure for use as C pin API
- add basic I2C driver, with init and writeto methods
- modpybi2c: add missing include
- clean up bit-bang I2C implementation
- implement bit-bang I2C read, and add i2c.readfrom method
- add onewire helper functions as C module
- add tests/onewire.py as a driver and test code for ds18b20 dev
- implement software SPI class
- add PWM support
- esppwm.c: fix IRQ handler prototype
- put lexerstr32.o into FlashROM
- put utils.o to FlashROM
- link ADC class into machine module
- add esp.neopixel_write function to bit-bang WS2812 data
- tests: add neopixel.py test
- put modpybi2c.o to FlashROM
- set up UART handling task soon into init process
- modesp: flash_write(): Writes in multiples of 4 bytes
- modesp: flash_read(): Accept buffer to read to as a second argument
- README: update for the current status of the port
- enable FatFs support
- esp8266.ld: put FatFs to FlashROM
- deploy: Use --flash_size=8m option to esptool.py
- moduos: add listdir() proxy for MP_STATE_PORT(fs_user_mount)[0]
- moduos: factor out VFS method proxy helper
- moduos: add os.remove(), proxying to VFS object
- zero out fs_user_mount state on (soft) reset
- support importing modules from filesystem
- implement os.urandom function
- add basic support for duplicating REPL output
- enable uos.dupterm() method
- esp_mphal: add support for debug UART-only output
- let esp8266 "os" messages go to standard (REPL) UART
- support synchronous wifi scanning
- fix issue when current REPL line was garbage-collected
- switch back to accumulating input data via ring buffer
- implement input part of dupterm handling
- reset term_obj on reboot
- move PHY mode constants from modesp to modnetwork
- disallow recursive calls to REPL
- support dedicated REPL loop (aka pull-style)
- switch to non event-driven REPL to support paste mode
- uart: get ctrl-C working now that event-based REPL is disabled
- use VM_HOOK to call ets_loop_iter within the VM
- README: add link to docs
- move .rodata where it belongs with -mforce-l32 help
- bump iROM size to 512k
- ets_alt_task: comment out debug output
- minimize gap between Inst/DataRAM segments and FlashROM segment
- switch back to flashing combined firmware (single file)
- update flashing instructions in README
- bump heap size to 24k
- move pyb.hard_reset() to machine.reset()
- move pyb.unique_id() to machine.unique_id()
- modnetwork: require_if(): Report the actual interface required
- make destination for vendor OS debug output soft-configurable
- add initial implementation of machine.UART
- README: add short troubleshooting section
- switch from terse error messages to normal ones
- implement multistage bootstrap sequence
- add esp.freemem() and esp.meminfo() functions
- implement mp_builtin_open() using vfs_proxy_call()

examples:
- http_client.py, http_server.py aren't just unix, move to network/
- http_client.py: improve CPython compatibility in stream mode
- http_client.py: introduce main() function
- http_server.py: refactor/simplify for Python 3.5
- http_server.py: introduce main() function
- http_server.py: bind to 0.0.0.0, to be accessible from other hosts
- http_client_ssl.py: HTTPS client example

docs:
- correct WiPy Timer docs
- minor change to improve clarity in machine.Timer docs
- add note on machine.Timer class regarding PWM output pins
- correct machine.Timer code examples related to duty cycle
- add esp8266 quick reference page, with basic info
- esp8266: minor tweaks to quickref, Timer and I2C classes
- add versions.html template and support code for a version sidebar
- allow list of versions to be specified by environment variable
- esp8266: fix indent errors, typos, and add info about REPL UART
- update asm_thumb2_hints_tips re return type of asm funcs
- update details on using ADCAll object for vref/vbat channels
- add Python speed optimisation guide, including minimal viper ref
- esp8266: update quick reference: i2c.readfrom and neopixel example
- update asm tutorial, maximum number of allowed args is now 4
- update pyb.I2C constructor to reflect changes in Pyboard Lite
- mention that pyb.SPI constructor accepts "X" and "Y" arguments
- update pyb.UART.any() to mention that it returns character count
- topindex.html: refer to "pyb" module only for pyboard
- add standard modules list for esp8266
- network: esp8266: Update docs on WLAN constructor
- more standard modules for esp8266
- esp: remove getaddrinfo(), now in socket module as expected
- esp8266/quickref: note that timers supported are virtual ones
- esp8266/quickref: add note about GPIO16
- esp8266: phy_mode() moved to network module
- esp8266: esp.wifi_mode() replaced with network.WLAN.active()
- esp8266: esp.mac() replaced with network.WLAN.mac()
- correct pin interrupt example code for the WiPy
- network: esp8266: status is WLAN object method
- network: esp8266: .scan() is now synchronous and returns result list
- update copyright notice
- esp8266: esp.socket is deprecated, remove from docs
- os: change wording to be a bit more port-neutral
- machine: change wording to be a bit more port-neutral
- ubinascii: document a2b_base64(), b2a_base64()
- esp8266/quickref: add note about physical vs logical pin numbers
- ubinascii: document non-standard "sep" argument to hexlify()
- esp8266: Enable "machine" module docs

IPv6 support in unix, bignum constant folding, urandom module, faster…

… VCP

In this release there are many bug fixes and consolidation of previous
features.  Constant folding in the parser can now operate on arbitrary
precision integers, and the inline assembler is no longer restricted to
using small-ints or 30-bits.  The urandom module has been added with the
most useful random functions included.  The uhashlib module now
implements SHA1.  The Unix port supports IPv6.  The stmhal port has much
faster USB VCP for board to PC transfers, and Timer(3) is now freed up
for general purpose use by the user.

py core:
- frozenmod: make frozen module content be 0-terminated
- frozenmod: store frozen module names together, to quickly scan them
- use polymorphic iterator type where possible to reduce code size
- make dir report instance members
- implement __dict__ for instances
- objstr: in str.format, handle case of no format spec for string arg
- parse: optimise away parse node that's just parenthesis around expr
- change mp_obj_int_is_positive to more general mp_obj_int_sign
- parse: improve constant folding to operate on small and big ints
- inlinethumb: allow assembler to use big ints as args to instructions
- inlinethumb: remove 30-bit restriction on movwt instruction
- viper: truncate viper integer args so they can be up to 32-bit
- emitglue: add more feature flags to .mpy persistent bytecode output
- mpz: fix conversion of float to mpz so it works on big endian archs
- objint: fix classification of float so it works for OBJ_REPR_D
- change type of .make_new and .call args: mp_uint_t becomes size_t
- change type signature of builtin funs that take variable or kw args
- change first arg of type.make_new from mp_obj_t to mp_obj_type_t*
- emitglue: use mp_obj_is_float instead of MP_OBJ_IS_TYPE
- use new code pattern for parsing kw args with mp_arg_parse_all
- add ustruct.pack_into and unpack_from
- modmicropython: add stack_use, heap_lock and heap_unlock functions
- inlineasm: add ability to specify return type of asm_thumb funcs
- runtime: mp_stack_ctrl_init() should be called immediately on startup
- formatfloat: add ability to format doubles with exponents > 99
- builtin property: accept keyword arguments

extmod:
- moduos_dupterm: make uos.dupterm() implementation reusable
- moduos_dupterm: make mp_uos_dupterm_tx_strn() function reusable
- moduos_dupterm: handle exceptions in call to dupterm's .write()
- fix uctypes size calculation for bitfields
- modurandom: add "urandom" module
- modurandom: make yasmarang() function static
- modurandom: add some extra random functions
- moduhashlib: add support for SHA1 (based on axTLS)
- moduhashlib: use MICROPY_PY_UHASHLIB_SHA1 config define
- moductypes: implement assignment for scalar array

tests:
- uctypes: test item assignment for scalar arrays
- object_dict.py: add test for obj.__dict__
- allow float tests to run when MATH_SPECIAL_FUNCTIONS is disabled
- fix math_fun_special test so it passes with single prec float
- remove builtin_dict test
- add some tests for urandom module
- update pyboard LED test
- for pyboard, add test for I2C error handling and recovery

minimal port:
- add enough code to run minimal build on STM32F4xx hardware

unix port:
- unix_mphal: handle exceptions in call to dupterm's .read()
- unix_mphal: be sure to wrap dupterm code with MICROPY_PY_OS_DUPTERM
- modtime: strftime(): Support 2nd argument, but as time_t value
- add socket.inet_ntop function
- allow to build coverage build with OBJ_REPR_D
- add option to build 64-bit NaN-boxing interpreter
- modffi: allow to compile modffi in OBJ_REPR_D mode
- modsocket: accept(): Make IPv6-clean
- modsocket: sockaddr(): Handle AF_INET6 addresses

windows port:
- enable urandom module

stmhal port:
- make stm constants big ints when they don't fit in a small int
- remove custom mod_machine_mem_get_{read,write}_addr functions
- add os.statvfs
- add support for building frozen files
- add support for the STM32F401NUCLEO board
- make USB CDC driver use SOF instead of TIM3 for outgoing data
- make TIM3 available for use by the user
- add PWM capability for LED(3) and LED(4) on pyboards
- in HAL I2C driver, move DMA setup to after sending I2C address

docs:
- fix readthedocs build by updating Latex params
- set author as 'Damien P. George and contributors'
- add link from pyboard switch tutorial to ISR rules document
- include extra functions in time documentation for pyboard
- several minor changes: network, pyb, ADCAll and inline asm
- update to say that Timer(3) is free, and detail LED intensity

travis:
- add unix NaN-boxing build to Travis builds
- switch to Ubuntu 14.04 Trusty

64-bit NaN-boxing, FreeDOS target, and PYBv1.1 and PYBLITEv1.0 boards

This release brings a new object model for 64-bit NaN-boxing on 32-bit
architectures, while allows double precision floating point numbers to
be used without allocating on the heap.  Unix and Windows ports have
better handling of Ctrl-C, and there is now a FreeDOS target within the
unix Makefile.  Windows (msvc) builds are now checked using Appveyor CI.
The stmhal port has new board config files for then next version of the
pyboard, PYBv1.1 and PYBLITEv1.0, as well as config files for the
STM32F429 discovery kit.  There is now delayed RTC initialisation with
LSI fallback, and DMA support for the SD card.  The DMA controllers are
turned off if DMA is idle for 100 msec or more, saving power.

py core:
- mpconfig.h: allow to build without alloca() for ANSI C compliance
- binary: make use of MP_ALIGN
- asmx86: fix function definition to use int32_t instead of int
- change mp_print_strn_t func type to use size_t for the str length
- change qstr_* functions to use size_t as the type for str len arg
- emit: change type of arg of load_const_obj from void* to mp_obj_t
- make mp_setup_code_state take concrete pointer for func arg
- use uintptr_t instead of mp_uint_t in MP_TAGPTR_* macros
- gc: move away from using mp_uint_t, instead use uintptr_t and size_t
- add MP_ROM_* macros and mp_rom_* types and use them
- wrap all obj-ptr conversions in MP_OBJ_TO_PTR/MP_OBJ_FROM_PTR
- add support for 64-bit NaN-boxing object model, on 32-bit machine
- mpprint: printing of doubles is now supported (by uPy own routine)
- gc: make GC block size be configurable
- mpconfig: actually allow to override MICROPY_BYTES_PER_GC_BLOCK
- fix function calls that have positional and a star-arg-with-iterator
- modsys: implement sys.modules
- make it easy to build without MICROPY_PY_BUILTINS_COMPLEX
- add MICROPY_PY_BUILTINS_MIN_MAX, disable for minimal ports
- add min/max "default" keyword argument
- don't try to optimise for+range when args are not simple expressions
- fix calling of parent classmethod from instance of subclass
- add mp_get_stream_raise to factor out check for stream methods
- mkrules.mk: don't pass COPT to linker
- emitinlinethumb: add support for MRS instruction
- make UNARY_OP_NOT a first-class op, to agree with Py not semantics
- fix compiler to handle lambdas used as default arguments
- modmath: add domain error checking to sqrt, log, log2, log10
- objpolyiter: implement instance-polymorphic iterator type
- gc: scan GC blocks as an array of pointers, not an array of objects
- gc: for finaliser, interpret a pointer into the heap as concrete obj
- gc: use size_t instead of mp_uint_t to count things related to heap
- mpprint: implement %llu and %lld format specifiers for mp_printf
- bc: use size_t instead of mp_uint_t to count size of state and args
- qstr: use size_t instead of mp_uint_t when counting allocated bytes
- qstr: change type of qstr from mp_uint_t to size_t
- parse: replace mp_int_t/mp_uint_t with size_t etc, where appropriate
- compile: use size_t or uintptr_t instead of mp_uint_t
- parse: include stddef.h for definition of size_t
- compile: simplify compilation of comprehension iterators
- emitglue: add include of unistd.h for read function
- add MICROPY_ENABLE_COMPILER and MICROPY_PY_BUILTINS_EVAL_EXEC opts
- gc: when printing info, use %u instead of UINT_FMT for size_t args
- obj: fix float constants for MICROPY_OBJ_REPR_C
- mpprint: fix printing of 64bit integers for 64bit windows builds
- objstr: make sure that b"%s" % b"foo" uses undecorated bytes value
- objstr: applying % (format) operator to bytes should return bytes, not str
- handle case of return within the finally block of try-finally
- be more restrictive binding self when looking up instance attrs
- map: add fast-path for hashing of map index when it is a qstr
- gc: improve mark/sweep debug output
- map: in map lookup, check for fixed map independent of ordered map
- nlr: use single preprocessor symbol to check if building on Windows

extmod:
- move fsusermount.c from stmhal for cross-port reuse
- fsusermount: make configurable with MICROPY_FSUSERMOUNT
- modmachine: use uintptr_t instead of mp_uint_t for address type
- moductypes: set_aligned(): Handle INT64/UINT64
- moductypes: sizeof operation depends on layout type of structure
- moduhashlib: add namespace prefix for crypto-algorithms/sha256.h
- modubinascii: add "separator" argument to hexlify()
- modlwip: tcp_recv: Use more regular and responsive poll pattern
- modlwip: mark some lwip_socket_obj_t's fields as volatile
- modlwip: user proper field name and value names for socket state
- modlwip: avoid magic numeric values in memcpy()
- modlwip: use _ERR_BADF instead of magic number

lib:
- utils/printf: apply workaround for static linking with uclibc
- utils/printf: add vsnprintf alias for Clang
- libm: allow math funcs to be used by non-Thumb archs
- utils: add pyexec_frozen_module to load and execute frozen module

tools:
- allow pyboard.py to work when boot.py prints things
- add option to pyboard.py to wait for serial device to be ready
- upgrade upip to 0.6.3; updated for _os -> uos builtin module rename
- add C middle-processor to make builtin tables proper hash tables

tests:
- run-tests: improve robustness of REPL tests
- extra_coverage: update for sys.modules addition
- run-tests: allow to skip complex tests if it's not compiled in
- add min/max "default" agrument test
- builtin_minmax: add testcase for lazy iterable (generator)
- add test for "not" of a user defined class
- add tests for %-formatting of bytes
- add tests for stream IO errors
- add test which demonstrates uctypes LITTLE_ENDIAN packing failure

unix port:
- unix_mphal: use size_t instead of mp_uint_t in stdout_tx_strn decls
- moduselect: fix bug in poll.poll() scanning loop
- moduselect: poll.register(): Reuse freed entries in poll array
- moduselect: support growing of poll array
- modtime: sleep(): automatically restart after receiving EINTR
- modtime: sleep(): return early if KeyboardInterrupt is pending
- mpconfigport.h: for MICROPY_NO_ALLOCA=1, don't even include alloca.h
- main: check pending exception at the end of code block execution
- moduselect: register(): allow to call with duplicate file descriptor
- modtermios: provide B57600 and B115200 constants only if defined
- moduselect: implement "one-shot" flag for poll.poll()
- rename "_os" module to "uos" for consistency with baremetal ports
- move modmachine into unix directory
- moduselect: make configurable with MICROPY_PY_USELECT
- modtime: add strftime() function (only single argument is supported)
- modos: implement ilistdir()
- modos: allow to configure use of d_ino using _DIRENT_HAVE_D_INO
- modos: add errno() function to get/set errno value
- add FreeDos target
- change define logic of _DIRENT_HAVE_D_INO to match other macros
- unix_mphal: properly initialize struct sigaction
- unix_mphal: just consistently set sigaction.sa_flags to 0
- machine_mem improvements
- properly cancel REPL input when Ctrl-C is pressed
- unix_mphal: raise KeyboardInterrupt straight from signal handler
- implement uos.dupterm(), conditional on MICROPY_PY_OS_DUPTERM

windows port:
- cleanup makefile
- support 64bit mingw-w64 builds
- make keyboard_interrupt_obj available, it's standard feature
- add basic support for raising KeyboardInterrupt
- add Appveyor CI builds for msvc port
- better handling of Ctrl-C
- msvc: nicer handling of asserts and 'invalid' parameters
- msvc: use different output directories depending on build type
- msvc: use new modmachine infrastructure per changes in f925165
- msvc: add dirent.h/.c implementation

stmhal port:
- implement delayed RTC initialization with LSI fallback
- put IRQs into priority order
- turn off DMA clocks when idle for 100 msec
- add dma support for sdcard
- on SysTick IRQ, only process one DMA channel at a time
- irq: add comment about SDIO priority being higher than DMA
- irq: set all IRQ subpriorities to 0, since they aren't used
- move flash storage idle tick handler from TIM3 to SysTick
- in SysTick IRQ handler, make uwTick variable non-volatile
- process storage idle tick handler in different slot to DMA
- increase the priority of UART IRQ
- add support for the STM32F429I-DISCO kit by STMicro
- allow make DEBUG=1 to build
- make stm.mem* support large integers
- uart.any() function now returns number of bytes available
- make uart.write() function correctly for timeout=0
- add board config files for PYBv1.1 and PYBLITEv1.0
- put all DMA channel & stream definitions in dma.h
- add raise_irq_pri and restore_irq_pri functions
- protect SD card DMA transactions against USB MSC contention
- add rtc.init() method to force RTC to re-initialise
- only use BASEPRI irq stuff if Cortex is M3 or higher
- add option to free up TIM3 from USB VCP polling
- fix uart off by 1 circular buffer size
- execute boot.py and main.py when formatting the file system
- print exception information in nlr_jump_failed
- enable two USB phys to be supported together
- timer: use mp_float_t instead of float
- for SPI config, use HW_SPIx_SCK instead of HW_ENABLE_SPIx
- make uart init use struct instead of array for parsing args
- extend SPI support to fully support all SPI devices on STM32F429
- moduselect: implement "oneshot polling" flag
- change PLL configuration for STM32F7DISC
- add mem8/mem16/mem32 operations to machine module
- add pyb.irq_stats() to get statistics about IRQ calls
- add struct qstr to block of qstrs needed for MICROPY_PY_STRUCT
- fix usbd_conf.c for devices which don't have USB_HS at all

cc3200 port:
- correct buffer offset in serial flash diskio module
- add __get_BASEPRI and __set_BASEPRI inline function definitions

esp8266 port:
- modesp: implement flash_read(offset, size_bytes) function
- mac() function belongs to network module per the latest API
- modesp: allow to compile out proprietary espconn stuff

docs:
- library: add network server example
- add discussion on interrupt handlers incl uPy specific techniques

pic16bit:
- use global MICROPY_NO_ALLOCA setting

ports:
- rename "machine" module to "umachine"

LwIP support, and preliminary implementation of persistent bytecode

This release includes the lwip network stack module with slip support.
There is a preliminary implementation of persistent bytecode which allows
to save compiled bytecode to a .mpy file, to be loaded at a later time by
another MicroPython instance.  Double precision floating-point formatting
is now provided by the core, and the bundled upip module is no longer
dependent on FFI.  stmhal port has improved RTC startup.  There are many
bug fixes and improvements to the documentation.

py core:
- makeversionhdr.py works with backslashes in paths
- in inline asm, vldr and vstr offsets now in bytes not words
- modstruct: support repetition counters for all types, not just string
- add py/mphal.h and use it in all ports
- adjust object repr C (30-bit stuffed float) to reduce code size
- clear finalizer flag when calling gc_free
- objint_longlong: instead of assert, throw OverflowError
- asmthumb: allow to compile with -Wsign-compare and -Wunused-parameter
- emitinlinethumb: allow to compile with -Wsign-compare
- reorganise bytecode layout so it's more structured, easier to edit
- put all bytecode state (arg count, etc) in bytecode
- add constant table to bytecode
- add MICROPY_PERSISTENT_CODE so code can persist beyond the runtime
- add MICROPY_PERSISTENT_CODE_LOAD/SAVE to load/save bytecode
- allow to import compiled bytecode files
- modmath: make expm1() be in MICROPY_PY_MATH_SPECIAL_FUNCTIONS
- compile: don't unnecessarily save state when compiling param list
- implement default and star args for lambdas
- modmath: make log2, log10 and hyperbolic funcs be SPECIAL_FUNCTIONS
- in mp_state_ctx_t, make mp_pending_exception volatile
- store key/value in earliest possible slot in hash table
- add Cygwin support to py/nlrx86.S
- add mp_compile_to_raw_code() to return raw code object
- emitglue: add mp_raw_code_load_mem to load raw-code from memory
- emitglue: host definition of mp_verbose_flag
- formatfloat: convert to fully portable implementation
- formatfloat: fix incorrect rounding for %f format
- formatfloat: handle calculation of integer digit for %f format properly
- mpz: normalize xor operation result to fix bugs in comparisons
- emitglue: add feature-flag header to .mpy to detect bytecode compat
- emitglue: implement persistent saving and loading of const objects
- check that second argument to hasattr is actually a string
- do proper checking of * and ** in function definition

extmod:
- modlwip: initial commit of the lwip network stack module
- modlwip: slip: Use stream protocol and be port-independent
- modlwip: lwip_tcp_send(): Common subexpression elimination, use MIN()
- modlwip: socket->incoming changed by async callbacks, must be volatile
- modlwip: change void pointers to unions, include new mphal.h file
- moductypes: implement buffer protocol
- moductypes: when dealing with UINT64, use mp_obj_new_int_from_ull()
- re1.5: update to 0.8, implements ?: and ??, as well as improved robustness
- re1.5: workaround issue with mingw32-gcc 4.2.1
- modure: make sure that errors in regexps are caught early

lib:
- lwip: add LwIP stack as a submodule in the library directory
- pyexec: for paste mode use "Ctrl" as the name of the key, not "CTRL"
- memzip: factor out memzip from teensy/ into lib/memzip
- mp-readline: make it easy to exit auto-indent mode by pressing enter
- fatfs: unify fatfs configuration
- pyexec: move header pyexec.h from stmhal directory
- utils/printf: move from stmhal/

tools:
- pyboard.py: make -c (inline Python code) option compatible with python2
- pyboard.py: don't add terminating \x04 character to stdout output
- update to upip 0.6.2: removes FFI dependency

tests:
- jni: test for basic object operations
- make sure test output has \r\n line-ends when running on Windows
- base/struct1.py: add test for repetition counters
- jni: add test for working with container of List interface
- float/string_format: add testcase for incorrect rounding for %f
- int_big_xor: test that xor result is normalized
- int_big_*: add more tests for result normalization

minimal port:
- use mp_hal_ticks_ms()
- add an explicit comment on the gchelper.s line in the Makefile

unix port:
- modjni: don't pass Java object to a method which doesn't expect it
- modjni: actually check argument type when doing method resolution
- gccollect: fallback to setjmp-based register fetching automatically
- modjni: add missing get_jclass_name() function
- allow to override MICROPY_PY_MATH_SPECIAL_FUNCTIONS from command-line
- switch stderr printing from ANSI C to native POSIX
- modos: add getenv()
- modos: add mkdir()
- modos: getenv(): Handle non-existing envvar correctly
- input: switch to POSIX I/O for history reading/writing
- add "uselect" module, with poll() function
- modsocket: implement sockaddr() function to decode raw socket address
- modsocket: use snprintf(), as defined by lib/utils/printf.c
- use printf() implementation in terms of mp_printf()
- main: get rid of perror() which uses stdio

windows port:
- do not use wildcards when looking in dirs containing optional features
- add usleep() implementation for msvc port
- REPL: erase pre-calc'd number of chars instead of clearing whole line
- rename "time" module to "utime" for consistency with others
- call _set_output_format() only on Visual Studio versions 2013 or lower
- use write() instead of fwrite() to avoid out-of-order output
- README: deprecate mingw32, suggest using mingw64
- update build instructions in the README
- fix project file for Visual Studio 2015
- allow specifying the python executable to use for msvc builds
- define ssize_t and use renamed mphal header

stmhal port:
- ffconf.h: include py/mpconfig.h
- fix USB_VCP.recv so that it returns actual amount of bytes read
- pyexec: use mp_hal_ticks_ms()
- moduselect: use mp_hal_ticks_ms()
- make accel AVDD pin configurable via mpconfigboard.h
- enable sdcard on STM32F7DISC board
- add define for UNIQUE_ID address (differs per MCU)
- make RTC init skip startup if LTE is already enabled and ready
- update PYBv3 and PYBv4 pin defs to include MMA pins, and others
- pyexec.c is common module, move to lib/utils/
- add symbolic #defines for interrupt levels in irq.h
- can: fix a bug in filter handling
- rtc: lSx oscillator is only initialized upon initial power up
- add missing regex property for parsing header comments
- print more information at HardFault time
- fatFS configuration moved to the library folder
- moduselect: expose POLLIN/OUT/ERR/HUP constants
- modmachine: initial attempt to add I2C & SPI classes

cc3200 port:
- add created sockets to the registry
- enable WLAN irq on creation
- allow to read pin value when in OPEN_DRAIN mode
- update README to change pyb to machine
- set pin direction first, then value
- fix bug in FTP command buffer, and set listening backlog to 0
- actually allow to specify a custom build directory
- switch from HAL_Delay() to mp_hal_delay_ms()
- switch from HAL_GetTick() to mp_hal_ticks_ms()
- use common pyexec.c
- fix SPI clock divider calculation
- make telnet server ignore NULL characters
- force SSL method to be TLSV1
- fatFS configuration moved to the library folder
- unmount all user file systems after a soft reset
- appsign.sh: use md5 if running under Darwin

teensy port:
- switch from HAL_* to mp_hal_* functions
- switch over to using frozen modules instead of memzip

esp8266 port:
- switch to standard mp_hal_*() functions

examples:
- add example of I2C usage, taking PyBoard accelerometer as subject

docs:
- add remark about ssl sockets and standard sockets
- correct machine.RTC examples
- explicitly specify behavior of UART stream protocol methods on timeout
- USB_VCP: Always in non-blocking mode, clarify stream method returns
- wipy: fix error in WLAN quickref
- wipy: fix several typos and change some pyboard to WiPy
- wipy: fix bug in example code and add note regarding OTA
- select: Describe poll.poll() return value in detail
- actually add unix port indexes, so docs for it could be generated
- library/index.rst: minimally adapt for unix port
- move instructions on generating the documentation to docs/README.md
- add docs about REPL paste-mode and Control-C
- select: document POLLIN/OUT/ERR/HUP
- update docs for WiPy wlan.connect()
- wipy: add warning about losing wlan connection when changing mode
- wipy: make wifi/wlan naming consistent with tutorial.rst

First-class REPL, ussl module, machine module for WiPy, stuffed-floats

This release brings first-class REPL support, which now has tab completion,
auto-indent, paste mode, history and _ to hold the last computed value.
There is a new ussl module, and one can now build a standalone unix binary.
The new machine API is implemented in cc3200, with the machine module and
additions to time and os modules.  stmhal contains the beginnings of this
new API, while still retaining full backwards compatibility with the original
pyb API.  unix also includes the new time functions, sleep_ms, sleep_us,
ticks_ms, ticks_us and ticks_diff.  A new object representation is available
which stores single-precision floats within a machine word (using 30-bit
precision), and allows to use float objects without the heap (not enabled in
any port).  There are also bug fixes and general improvements.

py core:
- put compiler state on the C stack
- objrange: bugfix for range_subscr() when index is a slice object
- parsenum: provide detailed error for int parsing with escaped bytes
- mpz: raise NotImplError instead of failing assertion
- mpz: force rhs of mpz_shl_inpl/mpz_shr_inpl to be unsigned
- mpz: fix bignum anding of large negative with smaller positive int
- catch all cases of integer (big and small) division by zero
- allocate parse nodes in chunks to reduce fragmentation and RAM use
- allow to enable inline assembler without native emitter
- fix edge case when constant-folding negation of integer
- emitnative: raise ViperTypeError for unsupported unary ops
- don't generate unnecessary parse nodes for assignment or kwargs
- factor logic when creating parse node from and-rule
- makeqstrdata.py: catch and report case of empty input file
- rename MP_BOOL() to mp_obj_new_bool() for consistency in naming
- add paste mode to friendly REPL, entered via CTRL-E
- rename "Micro Python" to "MicroPython" in REPL, help, readme's and misc
- objarray: allow to create array of void pointers, as extension to CPython
- move constant folding from compiler to parser
- make parser error handling cleaner, less spaghetti-like
- allow to to build MicroPython as a static library
- add support to call __init__ from a builtin module on first import
- implement ptr32 load and store in viper emitter
- fix calc of qstr memory usage, due to new qstr chunk allocation
- remove dependency on printf/fwrite in mp_plat_print
- fix with+for+return bug by popping for-iter when unwinding exc stack
- add option for inline assembler to support ARMv7-M instructions
- add support for _ in REPL to hold last computed value
- stream: allow to reuse is_nonblocking_error()
- add lsl/lsr/asr opcode support to inline Thumb2 assembler
- add mp_obj_is_float function (macro) and use it where appropriate
- move float e/pi consts to objfloat and make mp_obj_float_t private
- make float representation configurable with object representation
- add object repr "C", where 30-bit floats are stuffed in obj word
- nlrthumb: make compatible with Cortex-M0 (ARMv6M instr set)

extmod:
- add modussl, an SSL socket wrapper module based on axTLS

lib:
- axtls: add axtls git submodule, dependency of modussl
- libffi: add libffi as a submodule
- mp-readline: add n_chars argument to mp_hal_erase_line_from_cursor
- make netutils.h available to all ports by default

drivers:
- sdcard: allow up to 5 retries to initialise SD card

tools:
- upip: update to 0.5.9
- pyboard: add -c argument to run a program passed as a string

tests:
- wipy: improve robustness of time test
- wipy: improve robustness of rtc_irq test
- wipy: add machine module tests
- test slicing a range that does not start at zero
- add further tests for mpz code
- allow tests to pass against CPython 3.5
- add test for evaluation order of dictionary key/value pairs
- in pyb RTC tests, check wakeup register values
- add more tests for viper 16/32-bit load/store, and ellipsis
- jni: start adding modjni tests
- extmod: add tests for sleep_ms/us(), ticks_ms/us/diff()

unix port:
- modjni: new_jobject(): Handle null reference
- modjni: call_method(): If name doesn't match, cleanup via goto next_method
- modjni: call_method: Better resource release
- modjni: call_method: Delete done local references in loop
- modjni: implement len() for objects with java.util.List interface
- modjni: fix method argument matching
- modjni: propagate Java exceptions on list access
- modjni: convert Java's IndexOutOfBoundsException to Python's IndexError
- modjni: jobject.__str__/__repr__: Return Java .toString() value
- modjni: jclass.__str__/__repr__: Return Java .toString() value
- add support for building axtls dependency lib
- modjni: after Call*Method(), Java exception should always be checked
- modjni: allow to access fields of objects
- modjni: py2jvalue: Support bool and None values
- modsocket: fix usage of pointers to locals outside scope
- add exit and paste-mode hints to shell startup banner
- modtermios: tcsetattr: if 0 passed for "when" param, treat as TCSANOW
- modjni: call_method: check for Java exception after method return
- modjni: add iteration support for Java List objects
- allow to build against Android down to 1.5
- modos: add statvfs() function
- unix_mphal: implement HAL_Delay() and HAL_GetTick()
- modtime: implement sleep_ms(), sleep_us()
- modtime: implement ticks_ms(), ticks_us() and ticks_diff()
- modos: android Bionic lacks statvfs(), has BSD statfs()

stmhal port:
- in RTC.wakeup, fix setting of wucksel to get correct period
- fix RTC.wakeup so it correctly calculates WUT for large periods
- fix USB CDC-only mode under Windows
- enable REPL auto indent; document paste mode in help()
- allow to set bits resolution for DAC; 8 is default, can have 12
- make USB serial number actually be unique
- early version of machine module for stmhal
- add sleep_{ms,us} and ticks_{ms,us,cpu,diff} to time module
- implement os.dupterm (was pyb.repl_uart)
- uart: if char is not received within timeout, return EAGAIN error
- bring Pin class close to new machine module specification
- rtc: init uses YMD rather than backup register to detect powerup
- enable "all special methods" configuration option

cc3200 port:
- new irq API, affects all classes that provide the irq method
- new WLAN API including test
- implement support for os.dupterm()
- rename pyb module to machine
- disable uheapq and uhashlib
- make auth param positional in wlan.connect
- always reset WLAN after setting the mode
- wiPy SW v1.0.0 release
- in scan results rename 'auth' field to 'sec'
- create wipy module, remove HeartBeat class
- increase stack sizes a bit
- refactor network module to make the server a propper object
- WLAN class can retrieve the existing instance
- enable REPL autoindent
- uart.read() returns EGAIN if no chars available
- make socket.listen([backlog]) compliant with Python 3.5
- enable "all special methods" configuration option
- bump version to 1.1.0

docs:
- update esp8266 documentation to match the code
- describe properly how MCU can be woken from pyb.standby() state
- wipy: update all WiPy docs to reflect the new API
- wipy: add wipy and network.server documentation
- wipy: add wipy tutorials section
- wipy: add usocket and ussl modules' documentation
- wipy: several corrections to the classes in the machine module
- wipy: remove remaining references to 'af', which is now 'alt'
- wipy: add more tutorials and examples

misc:
- travis: build "deplibs" in unix port
- README: document "Ctrl-D" shell exit
- README: document how to enable/build external dependencies

Auto-indent for REPL, jni module for unix, lots more tests

py core:
- make frozensets hashable
- add MICROPY_PY_BUILTINS_FILTER to configure filter builtin
- make slice attributes (start/stop/step) readable (enable via
  MICROPY_PY_BUILTINS_SLICE_ATTRS)
- add support for array('q') and array('Q')
- add stream_tell method, and use for unix and stmhal file tell
- make string formatting 8-bit clean
- treat escaped quotes correctly in REPL continuation
- fix function args when a star-arg is followed by keyword args
- properly classify floats that look like hex numbers (eg 0e0)
- fix calculation of max digit storage for mpz; fix sys.maxsize
- refine SyntaxError for repeated use of global/nonlocal
- raise SyntaxError when unicode char point out of range
- fix error reporting for unexpected end of modulo format str
- fix error type for badly formatted format specifier (is now ValueError)
- raise NotImplementedError for unicode name escape instead of assert
- for str.endswith(s, start) raise NotImplementedError instead of assert
- make str.rsplit(None,n) raise NotImplementedError instead of assert
- handle 'raise X from Y' by issuing a warning that exception chaining is
  not supported
- make it_iternext() recognize IndexError
- only compile function annotations if really needed (for native emitter)
- simplify dispatch of bool binary op
- simplify printing of bytes objects when unicode enabled

lib:
- readline: add auto-indent support; 4 spaces are added at start of line
  to match previous indent, and if previous line ended in colon; backspace
  deletes 4 space if only spaces begin a line

drivers:
- nrf24l01: fix SPI phase setting to match specs of nRF chip

tools:
- upgrade upip to 0.5.8 (adds support for experimental ussl module)

tests:
- explain in README how tests get skipped
- add feature_check dir to collect capability detection scripts
- split byteorder-dependent tests to *_endian.py's
- allow to skip byteorder-dependent tests
- add escaped quotes tests for REPL
- add tests for bool, bytearray, float, exceptions (to improve coverage)
- add test for exception-chaining raise syntax
- add test on set/frozenset equality
- add tests for non-compliant behaviour (relative to CPython)
- add test where __getitem__ raises IndexError to stop iteration
- make io test cleanup after itself by removing 'testfile'
- move int+unicode test to unicode-specific test directory
- wipy: add I2C tests
- wipy: additional tests for when the UART is un-initialized
- wipy: improve UART tests with no pin assignment case
- wipy: remove unneeded dependencies to pyb.Pin

unix-cpy port:
- port is removed (no longer needed), along with conditional code in core

unix port:
- bump default heap size to 1MB (2MB on 64-bit systems)
- enable REPL auto-indent
- allow to build libffi from source and link against it
- add 'jni' module to interface to JNI-compliant JavaVM

windows port:
- make mpconfigport.h up-to-date with the unix port
- make unistd.h more posix compatible

stmhal port:
- use polling, not DMA, for 1 byte SPI transfers
- add 'opt' arg to pyb.main, to set mp_optimise_value
- add option to query for the current usb mode
- add support for STM32F411 Discovery Board (STM32F411E-DISCO)
- enable I & D caches for Cortex-M7
- fix single precision float printing error

cc3200 port:
- implement new Pin API
- implement new UART API
- implement new I2C API
- implement new SPI API
- implement new ADC API
- implement new WDT API
- implement new SD and RTC API plus os and time modules' extensions
- improve uniflash script and make it a bit more verbose
- increase error led blynk period to 100ms
- keep overwriting the same image on sequential updates
- improve file system check routine
- make sure to update sleep objects when registered
- reduce servers cycle time to improve FTP transfer rate
- remove unneeded loops in the FreeRTOS hooks
- server side SSL socket requires both certfile and keyfile
- don't clear the WDT special bit in the bootloader
- disable some uPy features in debug mode to help code fit
- change HeartBeat period from 5 to 4 seconds
- add mphal error to raise hardware related exceptions

esp8266 port:
- add wifi_mode() to read and set WiFi operating mode
- add wlan.isconnected() to maintain parity with other ports

docs:
- wipy: adapt ADC doc and quickref to the new API
- wipy: update I2C and UART docs to match the new API
- wipy: add pins to the I2C constructor

Lots of additions and improvements; support for STM32F2 and F7 MCUs.

py core:
- make showbc decode UNPACK_EX, and use correct range for unop/binop
- use wrapper to check self argument of builtin methods, to prevent seg faults
- remove mp_load_const_str and replace uses with inlined version
- remove mp_load_const_bytes and instead load precreated bytes object
- improve mp_import_name() debug logging
- catch case when relative import happens without active package
- fix running package submodule with -m
- add TimeoutError exception subclassed from OSError
- allow to build with debugging and bytearray but no array
- modstruct: Raise NotImplementedError for unsupported repeat specification
- REPL: Fix case where shorter names are shadowed by longer names
- prevent many extra vstr allocations by preallocating room for null byte
- improve allocation policy of qstr data (saves RAM)
- modbuiltins: Implement round() to precision
- make qstr hash size configurable, defaults to 2 bytes
- implement memoryview slice assignment, eg m1[0:3] = m2[2:5]
- viper: allow functions to take up to 4 arguments
- vipre: issue an error when compiling functions with more than 4 args
- raise SyntaxError when str hex escape sequence is malformed
- fix handling of parsing empty input so it raises an exception
- viper: compile errors now have traceback with function and filename
- REPL: don't look inside strings for unmatched brackets/quotes
- give more precise line number for compile errors (incl viper functions)
- make list += accept all arguments and add test
- makeversionhdr.py: Fallback to using docs version if no git repo

extmod:
- ubinascii: add a2b_base64 and b2a_base64 functions
- machine: implement physical memory access using /dev/mem (Linux, etc)

lib:
- readline: add emacs control chars for cursor movement (disabled by default)

drivers:
- onewire: fix ds18x20.read_temp so it works when no rom given

tools:
- update upip to 0.5.4: recognize and handle "package not found" error
- make-frozen.py: make Python2 compatibile
- pydfu.py: fix to work with old and new versions of PyUSB
- pyboard.py: fix parsing of returned error so last chr is not lost
- pyboard.py: make enter_raw_repl stricter and more reliable
- pyboard.py: speed up reading of chars by decreasing sleep period
- pyboard.py: add telnet support
- pyboard.py: make Python2 compatible

tests:
- add testcase for open(..., "a")
- adapt basics/memoryerror.py for ports with lower heap sizes
- adapt misc/features.py tests for ports without floating point
- add support for the WiPy in run-tests script (use --target to specify it)
- split out json float tests to separate files
- add test for relative import without package context
- skip parser test if "compile" builtin is not available
- use PTY when running REPL tests
- add test for pyboard SPI in slave mode, recv with no master
- test REPL emacs keys, but only if present
- always use forward slashes for paths (for Windows tests)
- fix exceptions when running cmdline tests on Windows
- Remove over-specification of startup banner

unix port:
- add O_WRONLY | O_CREAT to open call when opening file for append ("a")
- socket.getaddrinfo: accept family & socktype arguments
- socket.getaddrinfo: port is unsigned value
- modsocket: implement sendto(), recvfrom(), inet_pton()
- set MICROPY_PY_SYS_PLATFORM to "darwin" if compiled on OSX

stmhal port:
- modify dma_init() to accept init struct as an argument, making it more generic
- add config option for storage to use second flash segment (disable by default)
- add I2S support to make-pins.py
- add qstr definition for ifconfig when building for WizNet
- move HAL Cube files to f4/ subdir, keeping only those we use
- add STM32CubeF2 version 1.1.0, in hal/f2 directory
- add CMSIS device header files for STM32F2xx series
- allow DAC.write_timed to take Timer object in place of freq
- allow ADC.read_timed to take Timer object in place of freq
- check if user block device is mounted before accessing it
- put fs_user_mount pointer in root ptr section of global state (fixes crash)
- add hal and cmsis files from STM32Cube_FW_F7_V1.1.0
- add STM32F7DISC support
- factor out USRSW boot-up code and support boards with 1 LED
- factor GPIO clock enable logic into mp_hal_gpio_clock_enable
- add capability to print out info about a hard fault (disabled by default)
- fix make-pins.py to allow Port K
- add better support for UART having Tx and Rx on different ports
- add support for USART1 and conditional pins in make-pins.py
- add STM32F7 support for USB serial and storage
- enable I2C support for F7 MCUs
- enable SPI support for F7 MCUs
- fix hardfault when configured as a SPI slave
- generate modstm constants per build

cc3200 port:
- in Timer.callback() only use value param if in edge count mode
- create tools folder and add update-wipy.py script
- add deploy target and improve robustness of update-wipy.py
- enable more features to improve compatibility with stmhal
- add `Pin.name()` method
- adapt update-wipy.py timing to improve stability
- correct socket settimeout time format
- add CA, certificate and key files to the updater list
- add socket.timeout and socket.error exceptions
- raise an exception if trying to scan for networks in AP mode
- optimize check for WLAN AP mode
- set WLAN date/time via the rtc.datetime method()
- add modussl, ssl sockets subclassed from normal sockets
- time.sleep() now receives seconds, like CPython
- fix socket recv and recvfrom return value type
- enable base64 methods from modubinascii
- increment interrupt stack size from 2K to 3K
- create /flash/sys and /flash/lib directories while booting
- translate simplelink's socket error numbers to POSIX values
- use alternative HAL_Delay also when interrupts are disabled
- correct udelay us to ticks calculation
- increment telnet Tx retry delay on every try
- add struct weak link for ustruct
- set simplelink time and date when enabling WLAN
- refactor and clean-up socket closing code
- implement new OTA mechanism with 2 firmware update slots
- create /flash/cert folder if it doesn't exist
- make socket stream methods return POSIX error codes
- add socket.sendall() (aliases to send())
- rename pins from GPIO to just GP
- add socket.makefile()
- switch to 1 byte hash for QSTRs
- on ssl.read() or ssl.readall() ignore ssl layer closed error
- append last 2 bytes of the MAC address to the default SSID
- make I2C and SPI API the same as in stmhal
- add nic.iwconfig() to set/get WLAN configuration
- improve support for WEP security
- enable bootloader safe boot on latest firmware
- fix bug in ffconf regarding '/flash' string length
- add script to program the WiPy via UniFlash (windows only...)
- add factory smoke test as part of the tools
- speed up file system checking during start-up
- on the first boot, always make AP ssid='wipy-wlan'
- make ADC API compatible with the pyboard

esp8266 port:
- move scan() from esp module to network
- update the README.md to reflect what works
- move status() from esp module to network
- make pyb.RTC a type, and pyb.RTC() constructs an RTC object
- allow to easily override programming baudrate

docs:
- add more documentation for the CC3200 in the pyb module
- add "reference" directory for putting docs about the language
- add reference for Thumb2 inline assembler
- make index link point to "index.html" irrespective of port
- fix duplicate label error for network.WLAN
- update safe boot comments to match actual behaviour
- update pyb.Accel doc to reflect changes and explain filtered_xyz
- correct nic.ifconfig() quickref example
- add i2c keywork arguments only indication

Unix binary gets tab completion and builtin upip, and more.

py core:
- allow to compile without needing git to extract version
- conform to CPython's way of printing nan/inf with padding
- wrap qstr defs in quotes to protect from C preprocessor
- add stack check to mp_iternext to catch nested iterators
- implement implicit cast to obj for viper load/store index/value
- implement native multiply operation in viper emitter
- expose KeyboardInterrupt in builtins module
- fallback to stack alloca for Python-stack if heap alloc fails
- support unicode (utf-8 encoded) identifiers in Python source
- implement second arg for math.log (optional value for base)
- support mpz bignums in divmod builtin

extmod:
- add ubinascii.unhexlify
- swap address and descriptor args in uctypes constructor

lib:
- fix some issues with dates prior to 1 Mar 2000
- implemente delete key in readline

tools:
- pyboard.py: allow pyboard constructor to take a baudrate parameter
- pyboard.py: change logic for when raw ">" prompt is parsed
- add codestats.sh to compute code statistics such as size, speed

unix port:
- add option to use uPy readline and enable by default (adds tab completion)
- include upip as frozen module within standard uPy executable; standard
  way to use is: micropython -m upip install <module>
- allow to cat a script into stdin from the command line
- make micropython -m <module> work for frozen modules

windows port:
- implement mp_hal_xxx functions and enable uPy readline

stmhal port:
- raise error if disk is full when writing a file
- implement sys.stdin.buffer, sys.stdout.buffer for raw byte mode
- remove all PYBVxx defines and use general config vars instead
- add support for UART5 if MCU has it
- fix slow SPI DMA transfers by removing wfi from DMA wait loop
- break immediately from USB CDC busy wait loop if IRQs disabled
- make I2C transfers use DMA when possible (when IRQs are enabled)

cc3200 port:
- add os.rename()
- add Timer module
- add uhashlib with SHA1 and SHA256
- add ubinascii module
- implement full set of wake-on-WLAN features
- remove NIC abstraction layer
- improve WDT
- make peripheral API more similar to stmhal's
- improve reliability of ftp and telnet servers
- add antenna selection feature to WLAN
- add sendbreak method to UART

esp8266 port:
- add uos module
- allow to set CPU frequency to 160MHz using pyb.freq
- add pyb.ADC class
- to esp module add: mac, phy_mode, sleep_type, deepsleep, flash_id
- update SDK to version 1.1.0 (MIT licensed)
- fix lost chars when transfering large amounts of data over UART
- add skeleton "network" module with bare WLAN() constructor
- add WLAN.connect/disconnect functions
- change esp_scan to keep the current WiFi operating mode

docs:
- document esp module
- allow to generate separate docs for each port (using ..only directive)
- add initial docs for the WiPy

Tab autocompletion, and various improvements and bug fixes.

py core:
- add attrtuple for space efficient tuples with attr access
- add sys.implementation, with uPy name and version number
- fix printing of "inf" and "nan" values
- native: fix stack adjustment when erroring on binary op
- mpz: fix bug with shl not truncating zero digits correctly
- modify "with" implementation so it doesn't use any heap
- add sys.exc_info()
- implement conversion of bignum to bytes
- implement struct.pack with 'q' and 'Q' args on 32-bit archs
- replace py-version.sh with makeversiohdr.py, written in Python
- implement tab autocompletion for REPL
- rename struct module to ustruct
- add NotImplemented builtin constant
- handle user instance hash based on Python adhoc rules
- fix naming of function arguments when function is a closure
- fix printing of complex numbers with nan/inf

extmod:
- add machine module, with mem8, mem16, mem32 objects

lib:
- move common mod_network_* functions to lib/netutils
- move common time functions to lib/timeutils

tools:
- pyboard.py: add "--follow" option to wait for output indefinitely
- add script to install "upip" package manager

tests:
- add more viper tests, including for ViperTypeError
- coverage at 94%

unix port:
- modffi: support passing float/double args
- add special function to coverage build to improve coverage
- print unhandled exceptions to stderr

stmhal port:
- implement os.uname()
- reset timer counter to zero after changing auto reload
- properly disable unhandled timer interrupts
- automatically reenable IRQs when code drops to the USB REPL
- allow to configure UART pins completely via mpconfigboard.h
- make raw REPL work with event-driven version of pyexec
- add rtc.calibration() method to get/set RTC fine-tuning value
- add os.rename()
- add readinto() and readlines() methods to sys.stdin and pyb.USB_VCP

cc3200 port:
- add WiPy specific info to README.md
- fix byte order in MAKE_SOCKADDR and UNPACK_SOCKADDR
- select NIC when the socket is created
- add delays to allow ftp and telnet servers to start/stop
- make telnet login work with Tera Term
- implement os.uname()
- make WLAN scan results a list of attrtuples
- make WLAN.isconnected() also work in AP mode
- implement Sleep.wake_reason()
- make WLAN.ifconfig() return an attrtuple
- enable MICROPY_MODULE_WEAK_LINKS

esp8266 port:
- export station status() constants
- add esp.socket class, with ESP-style socket functionality
- add raw REPL support and working soft reset
- fix garbage collector by hard-coding stack end address
- add socket.onsent() callback support
- add support for frozen modules
- implement time functions
- add utime and pyb.RTC
- add module weak links

docs:
- document pyb.stop, pyb.standby, pyb.RTC.wakeup
- document USB_VCP read* and write methods

Improved native codegen, better printf, support for F401 and F411 MCUs.

py core:
- implement delete for property and descriptors
- add option to disable "enumerate" and "reversed" builtins
- can call functions with *args in native emitter
- implement full function arg passing for native emitter
- combine load_attr and store_attr internal type methods into one
- fix formatting of floating point numbers near 1.0
- support assignment of bytes to bytearray slices
- overhaul and simplify printf/pfenv mechanism
- fix builtin ord so that it can handle bytes values >= 0x80
- inlinethumb: add support for core floating point instructions
- make viper code generator raise ViperTypeError on error

lib:
- string0.c now in lib/libc/ (was in stmhal/)
- fatfs code size reduced (by 768 bytes on Thumb2 archs)

tests:
- more tests for builtins
- tests for lexer
- coverage increased to 93%

stmhal:
- make LED object print LED(x) for consistency with constructor
- in USB HID driver, make polling interval configurable
- allow sending CAN messages with timeout=0
- add support for sending and receiving CAN RTR messages
- make board parameters more configurable (HSE PLL, LED4, TIMs, etc)
- add support for F401 and F411 MCUs
- add support for Espruino Pico board
- make raw REPL mode 8-bit clean

cc3200 port:
- enable pull-ups for stdio UART pins
- enable long filename support in fatfs
- add WLAN.config_ip(), to assign a static IP
- add IPPROTO_SEC so secure sockets can be made

tools:
- make pyboard.py 8-bit clean, so it works with unicode chars

docs:
- document pyb.main() function