1. Make sure floating ip updates on vip ports affect the nsx LB
service, and avoids NAT rules
2. Make sure loadbalancer created with a pre-existing vip port
will also be affected by fip updates
3. prevent creation of multiple loadbalancers on teh same router
as the NSX backed does not allow it.
Change-Id: Ia4959b22a068b0053d7709e83c8809627e4f3e89