VOL-1670 - close and reestablish connections

When grpc connectivity to the core is broken the ofagent will
break the connection to ONOS and then work to reconnect to
the core. After connecting to the core the connection to
ONOS will be restablished.

Change-Id: I75e645de3784a64ef4f9992df8baf37959cbbd86
diff --git a/python/ofagent/main.py b/python/ofagent/main.py
index 58afe15..ec2ad0f 100755
--- a/python/ofagent/main.py
+++ b/python/ofagent/main.py
@@ -276,6 +276,7 @@
             args.enable_tls,
             args.key_file,
             args.cert_file).start()
+        Probe.connection_manager = self.connection_manager
         self.log.info('started-internal-services')
 
     @inlineCallbacks