Change the copyright back to the template (#98)

diff --git a/LICENSE.txt b/LICENSE.txt
index d62dda9..261eeb9 100644
--- a/LICENSE.txt
+++ b/LICENSE.txt
@@ -186,7 +186,7 @@
       same "printed page" as the copyright notice for easier
       identification within third-party archives.
-   Copyright 2016-2018 The Apache Software Foundation
+   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.