Added a messaging service implementation on top of IOLoop. Added ability to easily switch between netty and io loop (default is netty)

Change-Id: Id9af0756bf0a542f832f3611b486b2ac680b91e4
diff --git a/core/store/dist/src/main/java/org/onosproject/store/flowext/impl/DefaultFlowRuleExtRouter.java b/core/store/dist/src/main/java/org/onosproject/store/flowext/impl/DefaultFlowRuleExtRouter.java
index b609a3c..b7d69b2 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/flowext/impl/DefaultFlowRuleExtRouter.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/flowext/impl/DefaultFlowRuleExtRouter.java
@@ -51,7 +51,6 @@
 import org.onosproject.store.serializers.impl.DistributedStoreSerializers;
 import org.slf4j.Logger;
 
-import java.io.IOException;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.HashSet;
@@ -143,11 +142,7 @@
                       @Override
                       public void run() {
                           FlowExtCompletedOperation result = Futures.getUnchecked(f);
-                          try {
-                              message.respond(SERIALIZER.encode(result));
-                          } catch (IOException e) {
-                              log.error("Failed to respond back", e);
-                          }
+                          message.respond(SERIALIZER.encode(result));
                       }
                   }, futureListeners);
               }