leave re-scheduled volume status to creating

A re-scheduled volume should not be exported and set to available

Fixes bug #1159027

Change-Id: Ie61d9132ce1bd6461d5e4d9836424ebf14100389
Fix cinder-manage backup list to work with uuids

Fixes bug #1164922

Change-Id: I8ed7ff7ca334b983d60445d96cd1f6c368766407
Implement get_volume_stats for GlusterFS driver

Implement get_volume_stats(), so that the GlusterFS driver
will work correctly with the scheduler.

Fixes bug: 1164038

Change-Id: Ib4db8bad897212227b39704e2e6cb5f07f2bb70e
Remove update_volume_status log message from NFS driver

The manager logs an INFO message when this action occurs already,
and it not called by anyone else, so don't log twice:

INFO [cinder.volume.manager] Updating volume status
DEBUG [cinder.volume.drivers.nfs] Updating volume status

Change-Id: Id99be0c0e50837c2b59963d983b9a7db3d25919a
Merge "Remove update_volume_status log message from NFS driver"
Merge "Fix cinder-manage backup list to work with uuids"
Merge "Implement get_volume_stats for GlusterFS driver"