Creating a registry for gRPC services, early version restarts on each modification of the set of services.

Change-Id: I4ee69873508127ad5362563bc7f0e1c7ac4996aa
diff --git a/modules.defs b/modules.defs
index 40524a6..7e3ba3f 100644
--- a/modules.defs
+++ b/modules.defs
@@ -217,6 +217,7 @@
     '//apps/evpnopenflow:onos-apps-evpnopenflow-oar',
     '//apps/route-service:onos-apps-route-service-oar',
     '//apps/evpn-route-service:onos-apps-evpn-route-service-oar',
+    '//incubator/protobuf/registry:onos-incubator-protobuf-registry-oar',
 ]
 
 PROTOCOL_APPS = [