Previously, the API service created port objects without hitting the
conductor. This change moves port creation to the conductor service,
adding a create_port method.
Currently this just performs the port object creation but in a future
change this will be used to validate the physical network assignment of
ports in a portgroup when a port is created, ensuring that all ports in
the group have the same physical network.
The conductor RPC API version has been bumped to 1.41.
Change-Id: I7501bf9fedc668629d5b627475bb54fef5c6bf20
Partial-Bug: #1666009
9e3f412186