[ONOS-3222] Implement toString method for each Packet class

Change-Id: I17d72338d4202117d08b3dca9463be35a87a0c1e
diff --git a/utils/misc/src/test/java/org/onlab/packet/ndp/NeighborSolicitationTest.java b/utils/misc/src/test/java/org/onlab/packet/ndp/NeighborSolicitationTest.java
index 03e57f5e..6f8c9da 100644
--- a/utils/misc/src/test/java/org/onlab/packet/ndp/NeighborSolicitationTest.java
+++ b/utils/misc/src/test/java/org/onlab/packet/ndp/NeighborSolicitationTest.java
@@ -25,10 +25,7 @@
 import java.nio.ByteBuffer;
 
 import static org.hamcrest.Matchers.is;
-import static org.junit.Assert.assertArrayEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.assertThat;
-import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.*;
 
 /**
  * Tests for class {@link NeighborSolicitation}.
@@ -131,4 +128,15 @@
         assertTrue(ns1.equals(ns1));
         assertFalse(ns1.equals(ns2));
     }
+
+    /**
+     * Tests toString.
+     */
+    @Test
+    public void testToStringNS() throws Exception {
+        NeighborSolicitation ns = deserializer.deserialize(bytePacket, 0, bytePacket.length);
+        String str = ns.toString();
+
+        // TODO: need to handle TARGET_ADDRESS and Options
+    }
 }