Add keystone heat support

Heat provides heat::keystone::auth (heat-engine) and
heat::keystone::auth_cfn (cloudformation api) after [1].  This adds
support here

[1] https://review.openstack.org/#/c/45380/

Change-Id: Ib60620b2fcf2305283bd2a3475d78758fd664e22
Merge "Add keystone heat support"
Add possibility to change UCA repository

Instead of forcing 'updates' UCA repo, leaves possibility to the
operator to choose which UCA he wants for pulling packages

Change-Id: I3e47f8a8b280d1dfe29229e1f9905ad7c71c204d