Various code clean up.

resources/lang/en_US/intro.php

@@ -1,4 +1,6 @@
 <?php
+declare(strict_types=1);
+
 /**
  * intro.php
  * Copyright (c) 2017 thegrumpydictator@gmail.com
@@ -116,4 +118,4 @@ return [
 
     // create currency
     'currencies_create_code'                                  => 'This code should be ISO compliant (Google it for your new currency).',
-];
+];