[relnotes] Networking guide for Ocata
[relnotes] Networking guide for Ocata

Adds release notes for the Networking guide for Ocata.

Change-Id: Iac6e662514058ed48a89c67de0268d6bb41796e4

openstack/openstack-manuals,openstack/openstack-manuals,openstack/openstack-manuals,openstack/openstack-manuals