Use galera in HA all-in-one host group

This patch will use galera within the HA all-in-one host group. It also includes a custom puppet fact (galera_bootstrap_ok) that checks to see if any of the openstack databases exists. It can use this too bootstrap galera for a fresh deployment, in which case galera bootstrap will take place on the pacemaker control node.

Note that this depends on a previously merged patch that refactors the load balancer deployment such that haproxy will be up and running prior to any node trying to contact the database.
This is squashed patch of several commits. This has been tested on RHEL7.