This gives us the bare amount of features we need.  We can add work arounds
for older versions and lower the requirement but this should be a good
starting point.
Suggested-by: NDaniel Berrange <berrange@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
---
v1 -> v2
 - tremendous simplification suggested by danpb