Released v7.1.0

* Allow constraining versions globally without having to know exactly what will
  be installed by the pip command. :issue:`2731`.

* Accept --no-binary and --only-binary via pip.conf. :issue`2867`.

* Allow ``--allow-all-external`` within a requirements file.

* Fixed an issue where ``--user`` could not be used when ``--prefix`` was used
  in a distutils configuration file.

* Fixed an issue where the SOABI tags were not correctly being generated on
  Python 3.5.

* Fixed an issue where we were advising windows users to upgrade by directly
  executing pip, when that would always fail on Windows.

* Allow ``~`` to be expanded within a cache directory in all situations.

Released v7.0.3

* Fixed a regression where ``--no-cache-dir`` would raise an exception, fixes
  :issue:`2855`.

Released v7.0.2

* **BACKWARD INCOMPATIBLE** Revert the change (released in v7.0.0) that
  required quoting in requirements files around specifiers containing
  environment markers. (:pull:`2841`)

* **BACKWARD INCOMPATIBLE** Revert the accidental introduction of support for
  options interleaved with requirements, version specifiers etc in
  ``requirements`` files. (:pull:`2841`)

* Expand ``~`` in the cache directory when caching wheels, fixes :issue:`2816`.

* Use ``python -m pip`` instead of ``pip`` when recommending an upgrade command
  to Windows users.

Released v7.0.1

* Don't build and cache wheels for non-editable installations from VCSs.
* Allow ``--allow-all-external`` inside of a requirements.txt file, fixing a
  regression in 7.0.

Released v7.0.0

* **BACKWARD INCOMPATIBLE** Removed the deprecated ``--mirror``,
  ``--use-mirrors``, and ``-M`` options.

* **BACKWARD INCOMPATIBLE** Removed the deprecated ``zip`` and ``unzip``
  commands.

* **BACKWARD INCOMPATIBLE** Removed the deprecated ``--no-install`` and
  ``--no-download`` options.

* **BACKWARD INCOMPATIBLE** No longer implicitly support an insecure origin
  origin, and instead require insecure origins be explicitly trusted with the
  ``--trusted-host`` option.

* **BACKWARD INCOMPATIBLE** Removed the deprecated link scraping that attempted
  to parse HTML comments for a specially formatted comment.

* **BACKWARD INCOMPATIBLE** Requirements in requirements files containing
  markers must now be quoted due to parser changes from (:pull:`2697`) and
  (:pull:`2725`).  For example, use ``"SomeProject; python_version < '2.7'"``,
  not simply ``SomeProject; python_version < '2.7'``

* Ignores bz2 archives if Python wasn't compiled with bz2 support.
  Fixes :issue:`497`

* Support ``--install-option`` and ``--global-option`` per requirement in
  requirement files (:pull:`2537`)

* Build Wheels prior to installing from sdist, caching them in the pip cache
  directory to speed up subsequent installs. (:pull:`2618`)

* Allow fine grained control over the use of wheels and source builds.
  (:pull:`2699`)

* ``--no-use-wheel`` and ``--use-wheel`` are deprecated in favour of new
  options ``--no-binary`` and ``--only-binary``. The equivalent of
  ``--no-use-wheel`` is ``--no-binary=:all:``. (:pull:`2699`)

* The use of ``--install-option``, ``--global-option`` or ``--build-option``
  disable the use of wheels, and the autobuilding of wheels. (:pull:`2711`)
  Fixes :issue:`2677`

* Improve logging when a requirement marker doesn't match your environment
  (:pull:`2735`)

* Removed the temporary modifications (that began in pip v1.4 when distribute
  and setuptools merged) that allowed distribute to be considered a conflict to
  setuptools. ``pip install -U setuptools`` will no longer upgrade "distribute"
  to "setuptools".  Instead, use ``pip install -U distribute`` (:pull:`2767`).

* Only display a warning to upgrade pip when the newest version is a final
  release and it is not a post release of the version we already have
  installed (:pull:`2766`).

* Display a warning when attempting to access a repository that uses HTTPS when
  we don't have Python compiled with SSL support (:pull:`2761`).

* Allowing using extras when installing from a file path without requiring the
  use of an editable (:pull`2785`).

* Fix an infinite loop when the cache directory is stored on a file system
  which does not support hard links (:pull:`2796`).

* Remove the implicit debug log that was written on every invocation, instead
  users will need to use ``--log`` if they wish to have one (:pull:`2798`).

Released v6.1.1

* No longer ignore dependencies which have been added to the standard library,
  instead continue to install them.

Released v6.1.0

* Fixes :issue:`2502`. Upgrades were failing when no potential links were found
  for dependencies other than the current installation. (:pull:`2538`)

* Use a smoother progress bar when the terminal is capable of handling it,
  otherwise fallback to the original ASCII based progress bar.

* Display much less output when `pip install` succeeds, because on success,
  users probably don't care about all the nitty gritty details of compiling and
  installing. When `pip install` fails, display the failed install output once
  instead of twice, because once is enough. (:pull:`2487`)

* Upgrade the bundled copy of requests to 2.6.0, fixing CVE-2015-2296.

* Display format of latest package when using ``pip list --outdated``.
  (:pull:`2475`)

* Don't use pywin32 as ctypes should always be available on Windows, using
  pywin32 prevented uninstallation of pywin32 on Windows. (:pull:`2467`)

* Normalize the ``--wheel-dir`` option, expanding out constructs such as ``~``
  when used (:pull:`2441`).

* Display a warning when an undefined extra has been requested. (:pull:`2142`)

* Speed up installing a directory in certain cases by creating a sdist instead
  of copying the entire directory. (:pull:`2535`)

* Don't follow symlinks when uninstalling files (:pull:`2552`)

* Upgrade the bundled copy of cachecontrol from 0.11.1 to 0.11.2.
  Fixes :issue:`2481` (:pull:`2595`)

* Attempt to more smartly choose the order of installation to try and install
  dependencies before the projects that depend on them. (:pull:`2616`)

* Skip trying to install libraries which are part of the standard library.
  (:pull:`2636`, :pull:`2602`)

* Support arch specific wheels that are not tied to a specific Python ABI.
  (:pull:`2561`)

* Output warnings and errors to stderr instead of stdout. (:pull:`2543`)

* Adjust the cache dir file checks to only check ownership if the effective
  user is root. (:pull:`2396`)

* Install headers into a per project name directory instead of all of them into
  the root directory when inside of a virtual environment. (:pull:`2421`)

Released 6.0.8

* Fix an issue where the ``--download`` flag would cause pip to no longer use
  randomized build directories.

* Fix an issue where pip did not properly unquote quoted URLs which contain
  characters like PEP 440's epoch separator (``!``).

* Fix an issue where distutils installed projects were not actually uninstalled
  and deprecate attempting to uninstall them altogether.

* Retry deleting directories incase a process like an antivirus is holding the
  directory open temporarily.

* Fix an issue where pip would hide the cursor on Windows but would not reshow
  it.

Released v6.0.7

* Fix a regression where Numpy requires a build path without symlinks to
  properly build.

* Fix a broken log message when running ``pip wheel`` without a requirement.

* Don't mask network errors while downloading the file as a hash failure.

* Properly create the state file for the pip version check so it only happens
  once a week.

* Fix an issue where switching between Python 3 and Python 2 would evict cached
  items.

* Fix a regression where pip would be unable to successfully uninstall a
  project without a normalized version.

Released v6.0.6

* Continue the regression fix from 6.0.5 which was not a complete fix.