Added logging.hpp.
diff --git a/Makefile.in b/Makefile.in
index 26569c9..4e78d17 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -154,9 +154,9 @@
 am__v_lt_1 = 
 libndn_cpp_la_LIBADD =
 am_libndn_cpp_la_OBJECTS = ndn-cpp/common.lo ndn-cpp/data.lo \
-	ndn-cpp/interest.lo ndn-cpp/key.lo ndn-cpp/face.lo \
-	ndn-cpp/forwarding-entry.lo ndn-cpp/name.lo ndn-cpp/node.lo \
-	ndn-cpp/sha256-with-rsa-signature.lo \
+	ndn-cpp/face.lo ndn-cpp/forwarding-entry.lo \
+	ndn-cpp/interest.lo ndn-cpp/key.lo ndn-cpp/name.lo \
+	ndn-cpp/node.lo ndn-cpp/sha256-with-rsa-signature.lo \
 	ndn-cpp/encoding/binary-xml-element-reader.lo \
 	ndn-cpp/encoding/binary-xml-wire-format.lo \
 	ndn-cpp/encoding/wire-format.lo ndn-cpp/security/key-chain.lo \
@@ -166,7 +166,7 @@
 	ndn-cpp/transport/transport.lo \
 	ndn-cpp/transport/udp-transport.lo \
 	ndn-cpp/util/changed-event.lo \
-	ndn-cpp/util/dynamic-uchar-vector.lo
+	ndn-cpp/util/dynamic-uchar-vector.lo ndn-cpp/util/logging.lo
 libndn_cpp_la_OBJECTS = $(am_libndn_cpp_la_OBJECTS)
 PROGRAMS = $(bin_PROGRAMS)
 am_bin_test_encode_decode_data_OBJECTS =  \
@@ -507,10 +507,10 @@
   config.h \
   ndn-cpp/common.hpp ndn-cpp/common.cpp \
   ndn-cpp/data.cpp ndn-cpp/c/data.h ndn-cpp/data.hpp \
-  ndn-cpp/interest.cpp ndn-cpp/c/interest.h ndn-cpp/interest.hpp \
-  ndn-cpp/key.cpp ndn-cpp/c/key.h ndn-cpp/key.hpp \
   ndn-cpp/face.cpp ndn-cpp/face.hpp \
   ndn-cpp/forwarding-entry.cpp ndn-cpp/c/forwarding-entry.h ndn-cpp/forwarding-entry.hpp \
+  ndn-cpp/interest.cpp ndn-cpp/c/interest.h ndn-cpp/interest.hpp \
+  ndn-cpp/key.cpp ndn-cpp/c/key.h ndn-cpp/key.hpp \
   ndn-cpp/name.cpp ndn-cpp/c/name.h ndn-cpp/name.hpp \
   ndn-cpp/node.cpp ndn-cpp/node.hpp \
   ndn-cpp/publisher-public-key-digest.hpp \
@@ -532,6 +532,7 @@
   ndn-cpp/util/blob.hpp \
   ndn-cpp/util/changed-event.cpp ndn-cpp/util/changed-event.hpp \
   ndn-cpp/util/dynamic-uchar-vector.cpp ndn-cpp/util/dynamic-uchar-vector.hpp \
+  ndn-cpp/util/logging.cpp ndn-cpp/util/logging.hpp \
   ndn-cpp/util/signed-blob.hpp
 
 bin_test_encode_decode_forwarding_entry_SOURCES = tests/test-encode-decode-forwarding-entry.cpp
@@ -719,14 +720,14 @@
 	ndn-cpp/$(DEPDIR)/$(am__dirstamp)
 ndn-cpp/data.lo: ndn-cpp/$(am__dirstamp) \
 	ndn-cpp/$(DEPDIR)/$(am__dirstamp)
-ndn-cpp/interest.lo: ndn-cpp/$(am__dirstamp) \
-	ndn-cpp/$(DEPDIR)/$(am__dirstamp)
-ndn-cpp/key.lo: ndn-cpp/$(am__dirstamp) \
-	ndn-cpp/$(DEPDIR)/$(am__dirstamp)
 ndn-cpp/face.lo: ndn-cpp/$(am__dirstamp) \
 	ndn-cpp/$(DEPDIR)/$(am__dirstamp)
 ndn-cpp/forwarding-entry.lo: ndn-cpp/$(am__dirstamp) \
 	ndn-cpp/$(DEPDIR)/$(am__dirstamp)
+ndn-cpp/interest.lo: ndn-cpp/$(am__dirstamp) \
+	ndn-cpp/$(DEPDIR)/$(am__dirstamp)
+ndn-cpp/key.lo: ndn-cpp/$(am__dirstamp) \
+	ndn-cpp/$(DEPDIR)/$(am__dirstamp)
 ndn-cpp/name.lo: ndn-cpp/$(am__dirstamp) \
 	ndn-cpp/$(DEPDIR)/$(am__dirstamp)
 ndn-cpp/node.lo: ndn-cpp/$(am__dirstamp) \
@@ -789,6 +790,8 @@
 	ndn-cpp/util/$(DEPDIR)/$(am__dirstamp)
 ndn-cpp/util/dynamic-uchar-vector.lo: ndn-cpp/util/$(am__dirstamp) \
 	ndn-cpp/util/$(DEPDIR)/$(am__dirstamp)
+ndn-cpp/util/logging.lo: ndn-cpp/util/$(am__dirstamp) \
+	ndn-cpp/util/$(DEPDIR)/$(am__dirstamp)
 
 libndn-cpp.la: $(libndn_cpp_la_OBJECTS) $(libndn_cpp_la_DEPENDENCIES) $(EXTRA_libndn_cpp_la_DEPENDENCIES) 
 	$(AM_V_CXXLD)$(CXXLINK) -rpath $(libdir) $(libndn_cpp_la_OBJECTS) $(libndn_cpp_la_LIBADD) $(LIBS)
@@ -946,6 +949,7 @@
 @AMDEP_TRUE@@am__include@ @am__quote@ndn-cpp/transport/$(DEPDIR)/udp-transport.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@ndn-cpp/util/$(DEPDIR)/changed-event.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@ndn-cpp/util/$(DEPDIR)/dynamic-uchar-vector.Plo@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@ndn-cpp/util/$(DEPDIR)/logging.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@tests/$(DEPDIR)/test-encode-decode-data.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@tests/$(DEPDIR)/test-encode-decode-forwarding-entry.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@tests/$(DEPDIR)/test-encode-decode-interest.Po@am__quote@