remove copyright notice (#702)

Author: autoih

LICENSE

@@ -188,7 +188,7 @@ Copyright 2018 The TensorFlow Authors.  All rights reserved.
       same "printed page" as the copyright notice for easier
       identification within third-party archives.
 
-   Copyright 2019, The TensorFlow Authors.
+   Copyright [yyyy] [name of copyright owner]
 
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.