src: Update copyright notices for files modified in 2015

Change-Id: I44133f166a90e26887c1db8972aae651cdb72f01
Refs: #2352
diff --git a/src/util/ethernet.cpp b/src/util/ethernet.cpp
index aa6b058..c128d37 100644
--- a/src/util/ethernet.cpp
+++ b/src/util/ethernet.cpp
@@ -1,12 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /**
- * Copyright (c) 2014,  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) 2013-2015 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *