Propose Virt driver Objects Support

This adds a virt-objects-juno spec to represent the work that needs
to be done in the virt drivers to move to objects. I expect that
all the remaining work will be finished in Juno.

Related to blueprint virt-objects-juno

Change-Id: I467c8d7fb83a5a4a47bc2d6d83f64ec0c6722ce2
Merge "Propose Virt driver Objects Support"