Ansible roles to configure OpenStack services as Ceph clients.

Starting in the Octopus release, Ceph has its own day1 tool called
cephadm and it's own day2 tool called orchestrator which
will replace ceph-ansible. While ceph-ansible had the necessary features to configure Ceph clients, distributing config file and keyrings as necessary on nodes which aren't members of the Ceph cluster, neither cephadm or the orchestrator will manage Ceph clients configuration.

We will instead create new ansible roles in TripleO which will perform the Ceph clients (Nova, Cinder, Glance, Gnocchi) configuration, which is of special importance in TripleO to also support deployment scenarios in which the Ceph cluster is externally managed and not controlled by the undercloud, yet the OpenStack services configurations is.