CB-08: Use a community login service with campus login servers

One element of the campus bridging effort is to make it easier for campus IT administrators to move their users from local to community services (and vice versa). By having local researchers use a community login service to access campus login services, it becomes trivial to tell them to also use it to access community login services. Another element of campus bridging is to encourage campus ID administrators to make use of national services in lieu of developing their own services that do the same thing. Having campus admins use a community login service instead of building/operating their own reduces overall IT costs.