ONOS-509: Match IPV6_SRC, IPV6_DST criteria

* Following classes have been extended to match IPV6_SRC and IPV6_DST criteria:
    - Criteria
    - DefaultTrafficSelector
    - FlowEntryBuilder
    - FlowModBuilder

* Not included in this submission
    - Match of other IPv6-related criteria
    - Set of all IPv6-related criteria (action)

Change-Id: I115829a480356d2037e0fc809595f7a5eec25874
diff --git a/core/api/src/main/java/org/onosproject/net/flow/DefaultTrafficSelector.java b/core/api/src/main/java/org/onosproject/net/flow/DefaultTrafficSelector.java
index 1caed8e..756fdd7 100644
--- a/core/api/src/main/java/org/onosproject/net/flow/DefaultTrafficSelector.java
+++ b/core/api/src/main/java/org/onosproject/net/flow/DefaultTrafficSelector.java
@@ -184,6 +184,16 @@
         }
 
         @Override
+        public Builder matchIPv6Src(IpPrefix ip) {
+            return add(Criteria.matchIPv6Src(ip));
+        }
+
+        @Override
+        public Builder matchIPv6Dst(IpPrefix ip) {
+            return add(Criteria.matchIPv6Dst(ip));
+        }
+
+        @Override
         public Builder matchMplsLabel(Integer mplsLabel) {
             return add(Criteria.matchMplsLabel(mplsLabel));
         }