util+tests: fix copyright notices in files copied from NFD

Change-Id: I43fd6a6085cd5ffe99676e20d1cf55400577bdb7
diff --git a/tests/unit-tests/util/notification-stream.t.cpp b/tests/unit-tests/util/notification-stream.t.cpp
index 65522b0..3697c41 100644
--- a/tests/unit-tests/util/notification-stream.t.cpp
+++ b/tests/unit-tests/util/notification-stream.t.cpp
@@ -1,12 +1,12 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /**
- * Copyright (c) 2013-2017, Regents of the University of California,
- *                          Arizona Board of Regents,
- *                          Colorado State University,
- *                          University Pierre & Marie Curie, Sorbonne University,
- *                          Washington University in St. Louis,
- *                          Beijing Institute of Technology,
- *                          The University of Memphis
+ * Copyright (c) 2014-2017 Regents of the University of California,
+ *                         Arizona Board of Regents,
+ *                         Colorado State University,
+ *                         University Pierre & Marie Curie, Sorbonne University,
+ *                         Washington University in St. Louis,
+ *                         Beijing Institute of Technology,
+ *                         The University of Memphis.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *