BZ #1127863 - ceph client config

https://bugzilla.redhat.com/show_bug.cgi?id=1127863

Add parameters to controller and compute manifests to allow management
of:

  /etc/ceph/ceph.conf,
  /etc/ceph/ceph.client.images.keyring
  /etc/ceph/ceph.client.volumes.keyring

and add virsh secret-define for rbd