all: InterestHeader and ContentObjectHeader refactoring to Interest and ContentObject

refs #29
diff --git a/apps/ndn-consumer-cbr.h b/apps/ndn-consumer-cbr.h
index 01e84a5..6143268 100644
--- a/apps/ndn-consumer-cbr.h
+++ b/apps/ndn-consumer-cbr.h
@@ -45,13 +45,13 @@
 
   // From NdnApp
   // virtual void
-  // OnInterest (const Ptr<const InterestHeader> &interest);
+  // OnInterest (const Ptr<const Interest> &interest);
 
   // virtual void
-  // OnNack (const Ptr<const InterestHeader> &interest);
+  // OnNack (const Ptr<const Interest> &interest);
 
   // virtual void
-  // OnContentObject (const Ptr<const ContentObjectHeader> &contentObject,
+  // OnContentObject (const Ptr<const ContentObject> &contentObject,
   //                  const Ptr<const Packet> &payload);
 
 protected: