model+tracers: Implementing ability to trace satisfied/timed out interests

Implementing satsified/timed out interest tracing in L3AggregateTracer and L3RateTracer (only numbers)
diff --git a/model/fw/ndn-forwarding-strategy.h b/model/fw/ndn-forwarding-strategy.h
index b87b07d..a3fe5b5 100644
--- a/model/fw/ndn-forwarding-strategy.h
+++ b/model/fw/ndn-forwarding-strategy.h
@@ -501,6 +501,13 @@
 
   TracedCallback<Ptr<const ContentObject>, Ptr<const Packet>,
                   Ptr<const Face> > m_dropData;  ///< @brief trace of dropped Data
+
+  ////////////////////////////////////////////////////////////////////
+  ////////////////////////////////////////////////////////////////////
+  ////////////////////////////////////////////////////////////////////
+
+  TracedCallback< Ptr<const pit::Entry> > m_satisfiedInterests;
+  TracedCallback< Ptr<const pit::Entry> > m_timedOutInterests;
 };
 
 } // namespace ndn