Expose persistent serial numbers for local disks for OpenStack Compute (nova)

A guest querying the hardware properties of a disk will currently see a serial number for a volume, but not for a local disk (local root, ephemeral, or swap). This feature will add a persistent serial number for local disks.

Libvirt driver imagebackend refactor for OpenStack Compute (nova)

This blueprint proposes cleaning up libvirt driver's imagebackend code and it's callers in the driver module. Specifically the intention is to eliminate imagebackend.Image.cache() and replace it with 2 separate methods, create_from_func() and create_from_image(), to be implemented separately by each backend. cache()...