Stop neutron services more explicitly

After an unstack.sh several neutron services are left running. This
change tries to do a better (but not always successful) job of
stopping neutron agents.

stop_process does its own checking to see if a service is enabled
so we don't need to check before calling.

Change-Id: I8becbe9db56121cbc619a6d156b18f6c6d31a6e7
diff --git a/lib/neutron_plugins/services/metering b/lib/neutron_plugins/services/metering
index 51123e2..37ba019 100644
--- a/lib/neutron_plugins/services/metering
+++ b/lib/neutron_plugins/services/metering
@@ -23,7 +23,7 @@
 }
 
 function neutron_metering_stop {
-    :
+    stop_process q-metering
 }
 
 # Restore xtrace