Update redis to 3.2.0

[pyup-bot]

This PR updates redis from 3.1.0 to 3.2.0.

Changelog

3.2.0

* Added support for `select.poll` to test whether data can be read
   on a socket. This should allow for significantly more connections to
   be used with pubsub. Fixes 486/1115
 * Attempt to guarentee that the ConnectionPool hands out healthy
   connections. Healthy connections are those that have an established
   socket connection to the Redis server, are ready to accept a command
   and have no data available to read. Fixes 1127/886
 * Use the socket.IPPROTO_TCP constant instead of socket.SOL_TCP.
   IPPROTO_TCP is available on more interpreters (Jython for instance).
   Thanks Junnplus. 1130
 * Fixed a regression introduced in 3.0 that mishandles exceptions not
   derived from the base Exception class. KeyboardInterrupt and
   gevent.timeout notable. Thanks Christian Fersch. 1128/1129
 * Significant improvements to handing connections with forked processes.
   Parent and child processes no longer trample on each others' connections.
   Thanks to Jay Rolette for the patch and highlighting this issue.
   504/732/784/863
 * PythonParser no longer closes the associated connection's socket. The
   connection itself will close the socket. 1108/1085

Links

• PyPI: https://pypi.org/project/redis
• Changelog: https://pyup.io/changelogs/redis/
• Repo: https://github.com/andymccurdy/redis-py