Introduce client_args

client_args allow for users to manipulate the request without our init
being cluttered up with keyword args

[ci skip]

HISTORY.rst

@@ -18,6 +18,7 @@ History
 - ``endpoints.py`` now contains ``EndpointsMixin`` (rather than the previous ``api_table`` dict) for Twython, which enables Twython to use functions declared in the Mixin.
 - Added OAuth 2 authentication (Application Only) for when you want to make read-only calls to Twitter without having to go through the whole user authentication ritual (see docs for usage)
 - ``construct_api_url`` now accepts keyword arguments like other Twython methods (e.g. instead of passing ``{'q': 'twitter', 'result_type': 'recent'}``, pass ``q='twitter', result_type='recent'``)
+- Pass ``client_args`` to the Twython ``__init__`` to manipulate request variables. ``client_args`` accepts a dictionary of keywords and values that accepted by ``requests`` (`Session API <http://docs.python-requests.org/en/latest/api/#sessionapi>`_) [ex. headers, proxies, verify(SSL verification)] and the "request" section directly below it.
 
 2.10.1 (2013-05-29)
 ++++++++++++++++++