Expose VRRP router VRIDs for HA scenario

Expose the VRIDs assigned to the controller and swift VRRP groups
created in HA scenarios to allow users to avoid conflicts with existing
VRIDs in their environment.

Change-Id: I6c0c63dc9115f8fafbd78d00c9012011d900e0d5
Closes-Bug: #1280277
Merge "Expose VRRP router VRIDs for HA scenario"