[OC] add opencontrail admin

In order to stop using shared credentials a
separate contrail admin user has to be created.
This user will operate as admin in the same
admin tenant as keystone admin and will be
used with contrail services.

PROD-23356

Change-Id: Ife79c50282e637ee1a2fc4331eff0b518d2c66e2
3 files changed