This commit introduces support of V3 API and also removes token
regeneration every 1 hour which is totally unnecessary. Also,
token is now only stored in User model and passed to the
Keystone client via arguments, so there is no more two sources
of truth. User id and roles are also stored in User model now.
Partial-Bug: #1628445
Closes-Bug: #1618172
Depends-On: If201c247210131ce6ab192362eada250a4f51ce1
Change-Id: I48b73a09cad0d707c16df5ca8ada202173779129