This change adds a deployment script that can be used to migrate a
Ceph cluster deployed with the legacy openstack-helm-infra Ceph
charts to Rook. This process is disruptive. The Ceph cluster goes
down and comes back up multiple times during the migration, but the
end result is a Rook-deployed Ceph cluster with the original
cluster FSID and all OSD data intact.
Change-Id: Ied8ff94f25cd792a9be9f889bb6fdabc45a57f2e