Fetched information of total disk capacity from nova and added a new resource 'disk_capacity' to NovaClusterModelCollector cluster. Also a new resource type 'disk_capacity' was added to ResourceType. https://bugs.launchpad.net/watcher/+bug/1553124 Change-Id: I85750f25c6d2693432da8e5e3a3d0861320f4787 Closes-Bug: #1553124