Create authentication specific routes

These routes are purely based on your current authentication and bridge
the gap between what is available in the standard identity-api for
fetching scope targets based on user_id and what is required for the
federation APIs.

Implement /auth/projects /auth/domains and move /catalog to
/auth/catalog

Change-Id: I464c0ca5cc9f250d593340e9563de45b077dd4cd
Implements: blueprint auth-specific-data
Merge "Create authentication specific routes"