Change openstack-dev to openstack-discuss

Mailinglists have been updated. Openstack-discuss replaces
openstack-dev.

Change-Id: Ifdb408cadf02a22fb3a7c370235f28a371baaf3f

setup.cfg

@@ -4,7 +4,7 @@ summary = OpenStack Neutron Project Development Specs
 description-file =
     README.rst
 author = OpenStack
-author-email = openstack-dev@lists.openstack.org
+author-email = openstack-discuss@lists.openstack.org
 home-page = http://specs.openstack.org/openstack/neutron-specs/
 classifier =
     Intended Audience :: Developers