Added CAPABILITIES collection

Change-Id: I3610cb2f0f91bace613ac4fd44f0ee6e35dbce31
Fix issue 106.

The new vmsapi method to create vms arguments was not returning the created
object. We were dropping guest params this way.

Change-Id: I3738f336a4b930c624ae70157d9cd6bfd0e8902e
Merge remote-tracking branch 'upstream/stable/essex' into upmerge