A possible fix for #1036

I can only assume that the only possible thing to close on a session are the
adapters. As such, I wrote the close method for a session object which closes
all possible adapters.
Merge pull request #1037 from sigmavirus24/master

Fix #1036
Swap prepare_auth and prepare_body
Correctly identify cert files.

Resolves issue #1046.
Fix stupid, stupid logic error.
Why auth must be prepared last
Merge pull request #1048 from ib-lundgren/master

Swap prepare_auth and body
Import basestring.
Tweaked the 'data' param docs to indicate that a file-like object is also supported.
Updated API docs for 'data' param in sessions module to indicate that file-like object is also supported.
Merge pull request #1052 from hozn/apidocs-tweak

Small tweak to API docs to indicate that file-like object supported for data param.
Fixed typo in comment.
Merge pull request #1055 from michaelwheeler/patch-1

Fixed typo in comment.
Update session documentation.
Merge pull request #1049 from Lukasa/master

Correctly identify certificate filenames.
Merge pull request #1059 from Lukasa/sess_docs

Update session documentation.
Fixes url to AUTHORS.rst

and also mention using 'master' as development branch now.
Using 'master' branch for development

I'm assuming you're no longer using a 'develop' branch, as I don't see one on GitHub.
Merge pull request #1062 from philfreo/patch-2

Using 'master' branch for development
Merge pull request #1061 from philfreo/patch-1

Fixes url to AUTHORS.rst