The Control Plane Service Placement documentation connects network hosts
to networks listed in controller_network_host_network_interfaces.
However this only contained public, tunnel, and external networks. For a
fully functional network host, we also need:
- the overcloud admin network, to manage the host
- internal network, for services to interact with each other
- storage network, for manila-share
This change updates the default network configuration for network hosts
and adds a variable to define extra networks like for other hosts. It
also improves the documentation for adding network hosts.
Change-Id: I1bb857bfca9e209bc6de30ae9852a4a08b2c7fb0
58f26fb61b