Add support for neutronclient

The quantum_* modules will now try neutronclient first, and fall back
to quantumclient. If that fails, error out.

The code now references neutron instead of quantum in all internal
cases.
Specify internal_network_name

This allow one to specify a specific internal network name for the case
where there is more than one nic on an instance. Without this, the list
of ports may not return the correct order. Therefore, it is necessary
to specify the exact internal network to attach the floating ip to
Merge pull request #5322 from bcrochet/neutron-fip-select

quantum_* modules: Neutron name change, keeping backward compatibility