Container Support

The token authentication verification code needs to be refactored into a Django-REST-Framework compatible Authentication class.

Redirects to the content app need to contain a query parameter that will allow the content app to confirm that the user has permission to access the content it is requesting. This could possibly be the token also.

Once token auth is added back, all the tests that were disabled or modified need to be reverted to their original form so that token auth is being tested in CI. Revert this commit: https://github.com/pulp/pulp_container/commit/946eacfed12fa54aa89a3da293c4e03b3bb84580