1. Extract IPv4 address from standard port group attached to contrail
   vrouter VM as vRouter IP address to be used to send port attach
   and detach notifications
2. Ignore contrail vrouter VM since it does not need to be reflected
   in the VNC DB
3. Ignore distributed virtual portgroups attached to contrail dvswitch
   that do not have a PVLAN spec attached since those do not need
   to be reflected in the VNC DB

Change-Id: I1959a41eaebbd43a26e1161c4d8950e72e892818
Merge "1. Extract IPv4 address from standard port group attached to contrail    vrouter VM as vRouter IP address to be used to send port attach    and detach notifications 2. Ignore contrail vrouter VM since it does not need to be reflected    in the VNC DB 3. Ignore distributed virtual portgroups attached to contrail dvswitch    that do not have a PVLAN spec attached since those do not need    to be reflected in the VNC DB"