InterestPacket, ContentPacket, Face classes added

diff --git a/model/ndn_contentpacket.cc b/model/ndn_contentpacket.cc
new file mode 100644
index 0000000..6d64497
--- /dev/null
+++ b/model/ndn_contentpacket.cc
@@ -0,0 +1,8 @@
+//
+//  ndn_contentpacket.cpp
+//  Abstraction
+//
+//  Copyright 2011 UCLA. All rights reserved.
+//
+
+#include "ndn_contentpacket.h"