Puppet: Configure neutron_api_class on controller

Puppet: Configure neutron_api_class on controller

We're already configuring Neutron in Overcloud, but the controller
is still configured to use the default Nova neutron_api_class for
default configuration for networking, which means it used Nova Network
and not Neutron. This causes some of the Nova API is_neutron
checks to behave incorrectly.

This patch updates the controller to use nova::network::neutron (like
we already do on the overcloud_compute.pp role). As part of the change
several of the compute specific hiera settings for the
nova::network::neutron class have been moved to common.yaml.

Change-Id: Id2d5a5a0aa1ca087de714880ef1ea98484b06849