Switch to using the self-contained django_openstack_auth
package which is a proper django.contrib.auth pluggable
backend.
Notable functional improvements include:
* Better overall security via use of standard Django
auth code (well-vetted by security experts).
* Token expiration checking.
* User "enabled" attribute checking.
* Support for full range of Django auth attributes
such as is_anonymous, is_active, is_superuser, etc.
* Improved hooks for RBAC/permission-based acess control.
Regarding the RBAC/permission-based access control, this
patch moves all "role" and "service"-oriented checks to
permission checks. This will make transitioning to
policy-driven checking much easier once that fully lands
in OpenStack.
Implements blueprint move-keystone-support-to-django-auth-backend
Change-Id: I4f3112af797aff8c4c5e9930c6ca33a70e45589d
c339189b44