First minor maintenance release following mainnet

Grin mainnet

Minor Floonet update

Floonet release update

Re-launch floonet (mimblewimble#2249)

*  Fix secondary scaling bugs;  rename is_testnet -> is_floonet (mimblewimble#2215)
* add global::is_mainnet()
* use it to change pre-genesis pow type
* rename is_testnet -> is_floonet
* Support multiple chain configurations (mimblewimble#2217)
* Support multiple chain configurations
Supports generating the proper configuration for each chain type
(mainnet, floonet, usernet). Will run them by default under
their respective root directory (~/.grin/main, ~/.grin/floo, etc).
Assigned default ports for mainnet, overriding them to keep Floonet
ports unchanged.
For now, starting on mainnet will abort.
* Fixed usernet command line help message. Fixes mimblewimble#2217
* Differing magic numbers for each chain type (mimblewimble#2208)
* stick to e=H(R|P|m) when use schnorr signature (mimblewimble#2200)
* stick to e=H(R|P|m) when use schnorr signature
* (1)add verify_slate_messages for wallet receive (2)log the message content
* remove debug log on verify_slate_messages
* verify the sender's message signature when receive_tx in wallet listen
* Revert "remove debug log on verify_slate_messages"

This reverts commit 65ea32a.

* Revert "rustfmt"

This reverts commit c380ab9.

* Revert "(1)add verify_slate_messages for wallet receive (2)log the message content"

This reverts commit 9584ca7.

* [re-floonet] Keychain Floonet BIP32 version/network option (mimblewimble#2235)

* add 'is_floonet' property to keychain
* fix hex encoding and tests

* Fix couple floonet loose ends (mimblewimble#2230)

* Fix couple floonet loose ends. Fixes mimblewimble#2216
* Doc fix for sig message

* Refuse unkown kernel features (mimblewimble#2244)

* Minor: magic number change for re-floonet

* Set pre genesis is_secondary to true (mimblewimble#2247)

* Minor: tx validation error display underlying

* New floonet genesis

* genesis rustfmt

* Use chain-specific config for wallet toml gen

* Fix default wallet_listener_url

* New more reasonable genesis block, bumped version

* genesis rustfmt

* Couple minor fixes to genesis generation script

Testnet4, release 2, post hard-fork

Actually cleanup old blocks if archive_mode=false (mimblewimble#1814)

* actually cleanup old blocks if not in archive mode

* rustfmt

Testnet3 release version

testnet2 launch source tree