Start of serious reorganization

The whole forwarding logic is (will be) moved to the Forwarding Strategy
class.
diff --git a/apps/ccnx-producer.cc b/apps/ccnx-producer.cc
index 6d36eb3..8b57513 100644
--- a/apps/ccnx-producer.cc
+++ b/apps/ccnx-producer.cc
@@ -30,7 +30,7 @@
 
 #include "ns3/ccnx-app-face.h"
 #include "ns3/ccnx-fib.h"
-#include "../model/ccnx-fib-impl.h"
+// #include "../model/ccnx-fib-impl.h"
 
 #include <boost/ref.hpp>
 #include <boost/lambda/lambda.hpp>