Updates to the cgroups manifest to work on RHEL.

Add a new cgroup package parameter.

Update the cgroups.pp manifest to use the package params.

Also, updates the cgconfig.erb template to support Red Hat which
has slightly different cgroup mounts than Ubuntu.

Change-Id: I9bf34c93fe987c085040929ab16d5a5f5406ad47
Reviewed-on: https://review.openstack.org/18999
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Reviewed-by: Jeremy Stanley <fungi@yuggoth.org>
Reviewed-by: James E. Blair <corvus@inaugust.com>
Approved: James E. Blair <corvus@inaugust.com>
Tested-by: Jenkins