Use new synchronization helpers to avoid races when deploying with HA

There are a number of possible races when deploying neutron for the
first time:

 - when creating of the database / database user
 - when registering the endpoint and creating users in keystone
Manage neutron-server with pacemaker

We create the primitives/clone resources (protected with
crowbar_pacemaker_sync_mark) and we use the
Chef::Provider::CrowbarPacemakerService service provider.
Merge pull request #66 from vuntz/sync-marks

Use new synchronization helpers + manage services with pacemaker