Update copyright.

Author: mikewiebe

README.md

@@ -217,7 +217,7 @@ See [CHANGELOG](CHANGELOG.md) for a list of changes.
 ## <a name="license_info">License Information</a>
 
 
-Copyright (c) 2013-2017 Cisco and/or its affiliates.
+Copyright (c) 2013-2018 Cisco and/or its affiliates.
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.