all: InterestHeader and ContentObjectHeader refactoring to Interest and ContentObject

refs #29
diff --git a/examples/custom-strategies/custom-strategy.h b/examples/custom-strategies/custom-strategy.h
index 0c1fbf2..057669a 100644
--- a/examples/custom-strategies/custom-strategy.h
+++ b/examples/custom-strategies/custom-strategy.h
@@ -30,14 +30,14 @@
 protected:
   virtual bool
   DoPropagateInterest (Ptr<Face> incomingFace,
-                       Ptr<const InterestHeader> header,
+                       Ptr<const Interest> header,
                        Ptr<const Packet> origPacket,
                        Ptr<pit::Entry> pitEntry);
 
 public:
   virtual void
   DidSendOutInterest (Ptr<Face> inFace, Ptr<Face> outFace,
-                      Ptr<const InterestHeader> header,
+                      Ptr<const Interest> header,
                       Ptr<const Packet> origPacket,
                       Ptr<pit::Entry> pitEntry);