all: InterestHeader and ContentObjectHeader refactoring to Interest and ContentObject

refs #29
diff --git a/model/fw/flooding.cc b/model/fw/flooding.cc
index 0c369b7..3672b24 100644
--- a/model/fw/flooding.cc
+++ b/model/fw/flooding.cc
@@ -66,7 +66,7 @@
 
 bool
 Flooding::DoPropagateInterest (Ptr<Face> inFace,
-                               Ptr<const InterestHeader> header,
+                               Ptr<const Interest> header,
                                Ptr<const Packet> origPacket,
                                Ptr<pit::Entry> pitEntry)
 {