This adds task files for the backup, restore, and validation
for Redis. It also incorporates some of the foundational changes
from https://review.openstack.org/#/c/635506/
Change-Id: Idd50a6b53a22bc6b23df776cff9537e3c47618f3
These are a set of tasks to help facilitate backup and restore operations.
This includes preparing an external backup host, configuring SSH for
rsync, and some initial tasks for backing up and restoring a containerized
galera cluster. This should lay the foundation for further backup and
restore tasks.
Change-Id: If5c11956291205cd04a6ef9bdb3d221fcd970f24