user servicable snapshots

Change-Id: Idbf27dbe088e646a8ab81cedc5818413795895ea
Signed-off-by: Raghavendra Bhat <raghavendra@redhat.com>
Signed-off-by: Anand Subramanian <anands@redhat.com>
Signed-off-by: Raghavendra Bhat <raghavendra@redhat.com>
Reviewed-on: http://review.gluster.org/7700
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>