Commented out firewall_driver directive in nova.conf.  In recent
versions, this line causes Nova not to start.
Increase pause times for mariadb/galera.
Added additional comments surrounding the library directive, which is
different between MacOS & Fedora/RHEL.
Renamed primary_if to provider_if.
Merge pull request #1 from clarkhale/master

Small changes found while attempting to use Ansible at Aetna
Merge remote-tracking branch 'upstream/master' into aetna
Added additional flags for all.sample/prep.yml for using dns and rhn.

Additionally, removed the firewall sections from prep.yml, because
they were broken.
Changed call to grab controller names from controller_nodes structure.
Part of the goal of removing duplicate information from
controller_node_names.