Do not use Request._request anymore

For some reason we used `Request._request` originally when
processing the middleware for DOAC.  This is not needed, as the
Request object proxies all hits for unknown attributes to the
internal HttpRequest object.
Dropped non-markdown versions of the docs
Copy documentation down to /docs from /docs/markdown
Updated README with docs move
Added shebang and executable permission to runtests.py.
Added PEP8 configuration to setup.cfg.
Renamed test files.

In Django 1.6, the default test runner was changed to DiscoverRunner which
ignores files whose filenames do not start with “test”.

The imports in __init__.py files are no longer needed in Django 1.6, but I’ve
preserved them to maintain compatibility with previous versions.
Changed JSON exceptions’ status code.

According to the OAuth2 specification, when issuing an access token,
“The authorization server responds with an HTTP 400 (Bad Request)
status code (unless specified otherwise) […]”.
Merge pull request #6 from EE/test-running

Improved test running
Merge pull request #7 from EE/json-exception-code

Changed JSON exceptions’ status code.
Pull from PyPi from Django 1.6, update versions