model: Another set of refactoring/renaming to make code compile (not tested yet)

Refs #1005 (http://redmine.named-data.net/)
diff --git a/model/ndn-app-face.h b/model/ndn-app-face.h
index 4b47fda..5c88b4e 100644
--- a/model/ndn-app-face.h
+++ b/model/ndn-app-face.h
@@ -64,10 +64,10 @@
   ////////////////////////////////////////////////////////////////////
   // methods overloaded from Face
   virtual bool
-  SendInterest (Ptr<const Interest> interest, Ptr<const Packet> packet);
+  SendInterest (Ptr<const Interest> interest);
 
   virtual bool
-  SendData (Ptr<const ContentObject> data, Ptr<const Packet> packet);
+  SendData (Ptr<const ContentObject> data);
 
 public:
   virtual std::ostream&