Refactor ceph_monitoring.py
Refactor ceph_monitoring.py

The existing ceph_monitoring.py script uses the command 'ceph report' to
pull statistics from the Ceph cluster. This command can be relatively
resource intensive due to the volume of data returned [1] and so this
commit refactors the script to use several ceph sub-commands to pull the
relevant pieces of information.

[1] http://tracker.ceph.com/issues/11904

Issue: https://github.com/rcbops/rpc-openstack/issues/641

git-harry/rpc-openstack,rcbops/rpc-openstack,xeregin/rpc-openstack,sigmavirus24/rpc-openstack,major/rpc-openstack,darrenchan/rpc-openstack,sigmavirus24/rpc-openstack,byronmccollum/rpc-openstack,git-harry/rpc-openstack,mancdaz/rpc-openstack,xeregin/rpc-openstack,cfarquhar/rpc-openstack,major/rpc-openstack,cloudnull/rpc-openstack,shannonmitchell/rpc-openstack,byronmccollum/rpc-openstack,hughsaunders/rpc-openstack,hughsaunders/rpc-openstack,BjoernT/rpc-openstack,BjoernT/rpc-openstack,cloudnull/rpc-openstack,galstrom21/rpc-openstack,sigmavirus24/rpc-openstack,byronmccollum/rpc-openstack,cfarquhar/rpc-openstack,galstrom21/rpc-openstack,xeregin/rpc-openstack,shannonmitchell/rpc-openstack,prometheanfire/rpc-openstack,robb-romans/rpc-openstack,darrenchan/rpc-openstack,robb-romans/rpc-openstack,darrenchan/rpc-openstack,mancdaz/rpc-openstack,jacobwagner/rpc-openstack,prometheanfire/rpc-openstack,rcbops/rpc-openstack,darrenchan/rpc-openstack,xeregin/rpc-openstack,sigmavirus24/rpc-openstack,jacobwagner/rpc-openstack