NetAnim: Allow metadata as default in the examples

src/netanim/examples/dumbbell-animation.cc

@@ -94,6 +94,7 @@ int main (int argc, char *argv[])
 
   // Create the animation object and configure for specified output
   AnimationInterface anim (animFile);
+  anim.EnablePacketMetadata (); // Optional
   
   // Set up the acutal simulation
   Ipv4GlobalRoutingHelper::PopulateRoutingTables ();

src/netanim/examples/resources_demo.cc

@@ -179,7 +179,7 @@ int main (int argc, char *argv[])
 
 
   // Create the animation object and configure for specified output
-  pAnim = new AnimationInterface (animFile, true); // true --> Enable 3.105 behavior
+  pAnim = new AnimationInterface (animFile); 
   // Provide the absolute path to the resource
   resourceId1 = pAnim->AddResource ("/Users/john/ns3/netanim-3.105/ns-3-logo1.png");
   resourceId2 = pAnim->AddResource ("/Users/john/ns3/netanim-3.105/ns-3-logo2.png");

src/netanim/examples/wireless-animation.cc

@@ -174,7 +174,7 @@ main (int argc, char *argv[])
 
   AnimationInterface anim ("wireless-animation.xml"); // Mandatory
 
-  anim.EnablePacketMetadata (true); // Optional
+  anim.EnablePacketMetadata (); // Optional
   anim.EnableIpv4RouteTracking ("routingtable-wireless.xml", Seconds (0), Seconds (5), Seconds (0.25)); //Optional
   Simulator::Run ();
   Simulator::Destroy ();

src/netanim/model/animation-interface.h

@@ -454,7 +454,7 @@ public:
    * \param enable if true enables writing the packet metadata to the XML trace file
    *        if false disables writing the packet metadata
    */
-  void EnablePacketMetadata (bool enable);
+  void EnablePacketMetadata (bool enable = true);
 
   /**
    *