Remove LBaaS support from devstack

Devstack support for LBaaS is being migrated to an external
plugin in the neutron-lbaas repository.  The only LBaaS-
specific code that remains in devstack is a hook to support
existing configs that enable q-lbaas.  In that case, load
the external plugin if necessary.

Change-Id: I592f64407ccf1e722b8d9788917879d0236acf0b
Depends-On: I64a94aeeabe6357b5ea7796e34c9306c55c9ae67
diff --git a/stackrc b/stackrc
index cb044b8..103be6d 100644
--- a/stackrc
+++ b/stackrc
@@ -198,6 +198,9 @@
 NEUTRON_FWAAS_BRANCH=${NEUTRON_FWAAS_BRANCH:-master}
 
 # neutron lbaas service
+# The neutron-lbaas specific entries are deprecated and replaced by the neutron-lbaas
+# devstack plugin and should be removed in a future release, possibly as soon as Liberty.
+
 NEUTRON_LBAAS_REPO=${NEUTRON_LBAAS_REPO:-${GIT_BASE}/openstack/neutron-lbaas.git}
 NEUTRON_LBAAS_BRANCH=${NEUTRON_LBAAS_BRANCH:-master}