TUNNEL_ID field support in flow matching and actions

Change-Id: I886123a7c8d57dc4a3e12727ec8a9be4920da79e
diff --git a/core/api/src/main/java/org/onosproject/net/flow/DefaultTrafficTreatment.java b/core/api/src/main/java/org/onosproject/net/flow/DefaultTrafficTreatment.java
index 96abbe9..fe657e6 100644
--- a/core/api/src/main/java/org/onosproject/net/flow/DefaultTrafficTreatment.java
+++ b/core/api/src/main/java/org/onosproject/net/flow/DefaultTrafficTreatment.java
@@ -385,6 +385,11 @@
         }
 
         @Override
+        public Builder setTunnelId(long tunnelId) {
+            return add(Instructions.modTunnelId(tunnelId));
+        }
+
+        @Override
         public TrafficTreatment build() {
             //Don't add DROP instruction by default when instruction
             //set is empty. This will be handled in DefaultSingleTablePipeline