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.