The charm has cinder-backup listed as a core service which should always be
restarted on changes to config. However, cinder-backup is only present if
installed by the cinder-backup subordinate charm. The new pause/resume code
will put the charm in a blocked state in this case so it needs fixing.
This charm was not using some of the openstack charm conventions such as using
register_configs with resource_map and using hook_context rather context as
the key in resource map dict. These have been fixed.
Closes-Bug: 1563340
Change-Id: I2fd46e96e60dd60462a4ffa89f7f84e9fd31d234
f434b40b04