fw: Forwarder provides CS hit/miss counters

refs #4219

Change-Id: I7058c43bac4a5508d4b9907f6e684663b8953656
diff --git a/daemon/fw/forwarder.cpp b/daemon/fw/forwarder.cpp
index 9e0b8bb..69a93de 100644
--- a/daemon/fw/forwarder.cpp
+++ b/daemon/fw/forwarder.cpp
@@ -164,6 +164,7 @@
                               const Interest& interest)
 {
   NFD_LOG_DEBUG("onContentStoreMiss interest=" << interest.getName());
+  ++m_counters.nCsMisses;
 
   // insert in-record
   pitEntry->insertOrUpdateInRecord(const_cast<Face&>(inFace), interest);
@@ -195,6 +196,7 @@
                              const Interest& interest, const Data& data)
 {
   NFD_LOG_DEBUG("onContentStoreHit interest=" << interest.getName());
+  ++m_counters.nCsHits;
 
   data.setTag(make_shared<lp::IncomingFaceIdTag>(face::FACEID_CONTENT_STORE));
   // XXX should we lookup PIT for other Interests that also match csMatch?