We don't want nodepool to use floating IPs in the fn cloud as it is an
ipv6 only cloud. We explicitly tell it there is no fip source and that
the tenant network routes ipv6 externally. This config is based on the
limestone configuration which is a similar cloud network wise.
Change-Id: I4a27a22a5beb9c5fc9d3e16cd2ca5b41aecbb46f
7df5981e12