The LB VIP should be advertised by the Tier1 router only if it is on the
external network.
To do that, the global advertise vp flag will not be set, and instead a rule with a
filter to advertise only the VIPs on the external network is added.
In addition, an admin utility is added to update already existing routers with
loadbalancers.
Since VPNaaS also uses the router advertisement rules, its code was also updated so
that each application will handle only its own rules.
Change-Id: Ibfac0406a8c3009c323828cc42c96012e70cb0a9
b263b592b9