Adding a configuration option to prevent DHCP/Router edges sharing between
different tenants.
Also adding admin utilities for upgrade - redistribute the dhcp edges and
router edges if the configuration changed:
nsxadmin -r dhcp-binding -o nsx-redistribute
nsxadmin -r routers -o nsx-redistribute
Change-Id: I0d669c60413172a94ea5fc0beba0035df72c62ac