core: use ethernet::Address from ndn-cxx

refs #2142

Change-Id: I1258a0a1cadbedb31c506c69c84b7906a61fc761
diff --git a/core/network-interface.hpp b/core/network-interface.hpp
index 08824fa..baaa85b 100644
--- a/core/network-interface.hpp
+++ b/core/network-interface.hpp
@@ -1,11 +1,12 @@
 /* -*- 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
+ * 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
  *
  * This file is part of NFD (Named Data Networking Forwarding Daemon).
  * See AUTHORS.md for complete list of NFD authors and contributors.
@@ -20,13 +21,12 @@
  *
  * You should have received a copy of the GNU General Public License along with
  * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
- **/
+ */
 
 #ifndef NFD_CORE_NETWORK_INTERFACE_HPP
 #define NFD_CORE_NETWORK_INTERFACE_HPP
 
 #include "common.hpp"
-#include "ethernet.hpp"
 
 #include <net/if.h>