Restore docker variabes in ceph-base
Restore docker variabes in ceph-base

Since ceph-ansible doesn't support yet the container
generic variables already merged here, this change
restores the docker registry/image_tag/container values
to pull the right container from the registry.
This change can be reverted when the ceph-ansible PR
will be merged.

ceph-ansible PR: https://github.com/ceph/ceph-ansible/pull/4002

Change-Id: I5185371e92e7ea10489c7abfa89a24b12d67220b

openstack/tripleo-heat-templates,openstack/tripleo-heat-templates