Kafka Codec Integration

Made changes as per the comments on patch set 2.
Made changes as per comments on patch set 3.
Made further changes and event subscription works absolutely fine now.

Change-Id: Icd20195f6c0e045d14beb73584069d486ab9290c
diff --git a/apps/kafka-integration/app/pom.xml b/apps/kafka-integration/app/pom.xml
index 4e1d535..20b9427 100644
--- a/apps/kafka-integration/app/pom.xml
+++ b/apps/kafka-integration/app/pom.xml
@@ -166,6 +166,7 @@
                         com.fasterxml.jackson.core,
                         org.onlab.packet.*,
                         org.onosproject.*,
+                        org.onlab.util.*,
                         com.google.common.*
                     </Import-Package>
                     <Web-ContextPath>${web.context}</Web-ContextPath>