InterestPacket, ContentPacket, Face classes added

diff --git a/model/ndn_face.cc b/model/ndn_face.cc
new file mode 100644
index 0000000..c540eeb
--- /dev/null
+++ b/model/ndn_face.cc
@@ -0,0 +1,13 @@
+//
+//  ndn_face.cpp
+//  Abstraction
+//
+//  Copyright 2011 UCLA. All rights reserved.
+//
+
+#include "ndn_face.h"
+
+namespace ns3 
+{
+    
+}
\ No newline at end of file