Upgrade NFD/ndn-cxx to version 0.6.0

The upgrade required a small hotfix pushed to a custom github fork

Change-Id: I0f97f31739537e6274995022ea4d1a88aeedfb57
diff --git a/app/src/main/jni/nfd-android/custom-logger.hpp b/app/src/main/jni/nfd-android/custom-logger.hpp
index 2033967..86ed64c 100644
--- a/app/src/main/jni/nfd-android/custom-logger.hpp
+++ b/app/src/main/jni/nfd-android/custom-logger.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /**
- * Copyright (c) 2014-2016,  Regents of the University of California,
+ * Copyright (c) 2014-2017,  Regents of the University of California,
  *                           Arizona Board of Regents,
  *                           Colorado State University,
  *                           University Pierre & Marie Curie, Sorbonne University,
@@ -27,6 +27,7 @@
 #define NFD_ANDROID_CUSTOM_LOGGER_HPP
 
 #include "core/common.hpp"
+#include <sstream>
 #include <android/log.h>
 
 namespace nfd {