Add support in RDO for Freezer.


Freezer is a distributed backup restore and disaster recovery as a service platform. It is designed to be multi OS (Linux, Windows, OSX, *BSD), focused on providing efficiency and flexibility for block based backups, file based incremental backups, point-in-time actions, jobs synchronization (i.e. backup synchronization over multiple nodes) and many other features. It is aimed at being useful for all environments, including large ephemeral Clouds. Documentation and Code can be found at the following locations:


  https://github.com/openstack/freezer
  https://wiki.openstack.org/wiki/Freezer