Updated py-requests-oauthlib to 0.8.0.

v0.8.0 (14 February 2017)
+++++++++++++++++++++++++

- Added Fitbit compliance fix.
- Fixed an issue where newlines in the response body for the access token
  request would cause errors when trying to extract the token.
- Fixed an issue introduced in v0.7.0 where users passing ``auth`` to several
  methods would encounter conflicts with the ``client_id`` and
  ``client_secret``-derived auth. The user-supplied ``auth`` argument is now
  used in preference to those options.

(wiz)