Update Dutch language files [skip ci]

resources/lang/nl_NL/intro.php

@@ -1,9 +1,8 @@
 <?php
-declare(strict_types=1);
 
 /**
  * intro.php
- * Copyright (c) 2017 thegrumpydictator@gmail.com
+ * Copyright (c) 2018 thegrumpydictator@gmail.com
  *
  * This file is part of Firefly III.
  *
@@ -21,6 +20,8 @@ declare(strict_types=1);
  * along with Firefly III. If not, see <http://www.gnu.org/licenses/>.
  */
 
+declare(strict_types=1);
+
 return [
     // index
     'index_intro'                           => 'Welkom op de homepage van Firefly III. Neem even de tijd voor deze introductie zodat je Firefly III leert kennen.',