adds dependencies and settings to install oauth library
changes canvas api to use oauth library
Creates library to facilitate django oauth with canvas in order to get a token for the SDK.

Tokens are per django user.

This version of the library is still dependent on django-auth-lti middleware
Merge branch 'feature/oauth_library' into feature/oauth_integration

Conflicts:
	ab_testing_tool/urls.py
fix
fix
adds patch so tests pass
adds rauth dependency back in
updates release on django-auth-lti
Merge pull request #52 from penzance/feature/oauth_integration

Integrates OAuth