Added unit test for Match and UpdateResult + Javadoc fixes

Change-Id: I8dae6c9568d33d580d60a72fdcc1be45b7308727
diff --git a/core/api/src/main/java/org/onosproject/store/service/TransactionException.java b/core/api/src/main/java/org/onosproject/store/service/TransactionException.java
index 6135394..a3723ee 100644
--- a/core/api/src/main/java/org/onosproject/store/service/TransactionException.java
+++ b/core/api/src/main/java/org/onosproject/store/service/TransactionException.java
@@ -20,7 +20,7 @@
  * Top level exception for Transaction failures.
  */
 @SuppressWarnings("serial")
-public class TransactionException extends RuntimeException {
+public class TransactionException extends StorageException {
     public TransactionException() {
     }