Don’t raise AuthenticationFailed if user didn’t try to authenticate.
Added tests for Django Rest Framework authentication integration.
Merge pull request #5 from EE/rest_framework-authentication

Don’t raise AuthenticationFailed if user didn’t try to authenticate.
Split up the tests for AuthorizationToken
Cleaned up some tests
Add Django 1.6 to the tests
Fix the exclusion for Python 2.6 on the Django master