This commit adds additional control around how the galera cluster
nodes are restarted during an upgrade (both the openstack upgrade
as well as mariadb upgrade). lxc config that gets added during the
lxc-container-create play would normally force a container restart.
This commit essentially does the following:
- run lxc-container-create on galera nodes but prevent container restarts
from being triggered by the new lxc config that gets laid down
- run a mariadb upgrade
- run a controlled rolling restart of all mariadb cluster containers
Change-Id: I5d979eb15c471274cc14ce6f41c8ae479c5131d6