message: chore(license): Updated year range to 2018
diff: same "printed page" as the copyright notice for easier
  identification within third-party archives.
  - Copyright (c) 2015-2017 Google, Inc., Netflix, Inc., Microsoft Corp. and contributors
  + Copyright (c) 2015-2018 Google, Inc., Netflix, Inc., Microsoft Corp. and contributors
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  