fixes #1574 - ovirt - add remove and show volumes

• volume and interface ordering is now working
• removed include blank because it is a duplicate of the Blank ovirt-template.
• bootable is disabled when editing a vm, because currently I don't handle volume updates. just add and remove of a volume.
• Volumes are created in the order that they where created in the gui. Bootable is set by default to the first volume.
• update to the latest rbovirt gem.