ONOS-635 Adding ICMPv6 type and code builder for HostMonitor.

aovid duplicate call of toString.

Apply changes to FlowEntryBuilder and FlowModBuilder as well.
Fix missing break; issue.

Change-Id: I1a2e59ca943bbcc9677b9fc0cb9eb2f7cb3d7aa3
diff --git a/core/api/src/main/java/org/onosproject/net/flow/TrafficSelector.java b/core/api/src/main/java/org/onosproject/net/flow/TrafficSelector.java
index 267fb51..e483043 100644
--- a/core/api/src/main/java/org/onosproject/net/flow/TrafficSelector.java
+++ b/core/api/src/main/java/org/onosproject/net/flow/TrafficSelector.java
@@ -163,6 +163,22 @@
         public Builder matchIPv6Dst(IpPrefix ip);
 
         /**
+         * Matches a ICMPv6 type.
+         *
+         * @param icmpv6Type a ICMPv6 type
+         * @return a selection builder
+         */
+        public Builder matchIcmpv6Type(Byte icmpv6Type);
+
+        /**
+         * Matches a ICMPv6 code.
+         *
+         * @param icmpv6Code a ICMPv6 code
+         * @return a selection builder
+         */
+        public Builder matchIcmpv6Code(Byte icmpv6Code);
+
+        /**
          * Matches on a MPLS label .
          * @param mplsLabel a MPLS label.
          * @return a selection builder