Log Message:
Update py-requests to 2.8.1.

2.8.1 (2015-10-13)
++++++++++++++++++

**Bugfixes**

- Update certificate bundle to match ``certifi`` 2015.9.6.2's weak certificate
  bundle.
- Fix a bug in 2.8.0 where requests would raise ``ConnectTimeout`` instead of
  ``ConnectionError``
- When using the PreparedRequest flow, requests will now correctly respect the
  ``json`` parameter. Broken in 2.8.0.
- When using the PreparedRequest flow, requests will now correctly handle a
  Unicode-string method name on Python 2. Broken in 2.8.0.

2.8.0 (2015-10-05)
++++++++++++++++++

**Minor Improvements** (Backwards Compatible)

- Requests now supports per-host proxies. This allows the ``proxies``
  dictionary to have entries of the form
  ``{'<scheme>://<hostname>': '<proxy>'}``. Host-specific \ 
proxies will be used
  in preference to the previously-supported scheme-specific ones, but the
  previous syntax will continue to work.
- ``Response.raise_for_status`` now prints the URL that failed as part of the
  exception message.
- ``requests.utils.get_netrc_auth`` now takes an ``raise_errors`` kwarg,
  defaulting to ``False``. When ``True``, errors parsing ``.netrc`` files cause
  exceptions to be thrown.
- Change to bundled projects import logic to make it easier to unbundle
  requests downstream.
- Changed the default User-Agent string to avoid leaking data on Linux: now
  contains only the requests version.

**Bugfixes**

- The ``json`` parameter to ``post()`` and friends will now only be used if
  neither ``data`` nor ``files`` are present, consistent with the
  documentation.
- We now ignore empty fields in the ``NO_PROXY`` enviroment variable.
- Fixed problem where ``httplib.BadStatusLine`` would get raised if combining
  ``stream=True`` with ``contextlib.closing``.
- Prevented bugs where we would attempt to return the same connection back to
  the connection pool twice when sending a Chunked body.
- Miscellaneous minor internal changes.
- Digest Auth support is now thread safe.

**Updates**

- Updated urllib3 to 1.12.