extends gerrit acls to allow creation of stable branches
extends gerrit acls to allow creation of stable branches

- allows creations of stable branches
  for the stackforge/networking-ovs-dpdk repo
- extened permissions of networking-ovs-release
  group to allow creation of branches.
- restricts label-workflow on stable branches to
  networking-ovs-release group

Change-Id: I0e470207920652becbf14843b5f9ebf7aae0d1b0

openstack-infra/project-config,openstack-infra/project-config,coolsvap/project-config,anbangr/osci-project-config,Tesora/tesora-project-config,dongwenjuan/project-config,noorul/os-project-config,noorul/os-project-config,dongwenjuan/project-config,Tesora/tesora-project-config,coolsvap/project-config,citrix-openstack/project-config,citrix-openstack/project-config,anbangr/osci-project-config