all: InterestHeader and ContentObjectHeader refactoring to Interest and ContentObject

refs #29
diff --git a/utils/tracers/ndn-cs-tracer.cc b/utils/tracers/ndn-cs-tracer.cc
index 2200665..80afe64 100644
--- a/utils/tracers/ndn-cs-tracer.cc
+++ b/utils/tracers/ndn-cs-tracer.cc
@@ -173,13 +173,13 @@
 }
 
 void 
-CsTracer::CacheHits (Ptr<const InterestHeader>, Ptr<const ContentObjectHeader>)
+CsTracer::CacheHits (Ptr<const Interest>, Ptr<const ContentObject>)
 {
   m_stats.m_cacheHits ++;
 }
 
 void 
-CsTracer::CacheMisses (Ptr<const InterestHeader>)
+CsTracer::CacheMisses (Ptr<const Interest>)
 {
   m_stats.m_cacheMisses ++;
 }