Separate interfaces for swift and OpenStack VIPs

Adjust the data mappings to allow for separate interfaces to be used for
swift and OpenStack VIPs on load balancers in an HA deployment.

Change-Id: Iced28a9a4e5fa6b3492dd407f9164b67dec64434
Partial-Bug: #1287935
Merge "Separate interfaces for swift and OpenStack VIPs"