all: InterestHeader and ContentObjectHeader refactoring to Interest and ContentObject

refs #29
diff --git a/examples/custom-apps/custom-app.h b/examples/custom-apps/custom-app.h
index 1ae1f4f..0d33bd8 100644
--- a/examples/custom-apps/custom-app.h
+++ b/examples/custom-apps/custom-app.h
@@ -54,11 +54,11 @@
 
   // (overridden from ndn::App) Callback that will be called when Interest arrives
   virtual void
-  OnInterest (const Ptr<const ndn::InterestHeader> &interest, Ptr<Packet> origPacket);
+  OnInterest (const Ptr<const ndn::Interest> &interest, Ptr<Packet> origPacket);
 
   // (overridden from ndn::App) Callback that will be called when Data arrives
   virtual void
-  OnContentObject (const Ptr<const ndn::ContentObjectHeader> &contentObject,
+  OnContentObject (const Ptr<const ndn::ContentObject> &contentObject,
                    Ptr<Packet> payload);
 
 private: