Progress toward issue #2003.
Includes design from design doc PR #1578

Use init containers to create configuration for Ceph mgrs. There is only
1 init container in this design:
 1. Using the Rook image, call the Rook binary to create Ceph config
files shared with the mgr daemgr container.

Once this init is run, the main mgr daemgr is run. Leaving room to use
the Ceph-versioned image in the future, call `ceph-mgr --foreground ...`
to run the Ceph mgr.
Signed-off-by: Blaine Gardner <blaine.gardner@suse.com>