My first translation update

Cherry-picked from !826 after master change.

Author: helmo

interface/web/tools/lib/lang/nl_index.lng

@@ -1,4 +1,4 @@
 <?php
 $wb['page_head_txt'] = 'ISPConfig Tools';
-$wb['page_desc_txt'] = 'Change user settings';
+$wb['page_desc_txt'] = 'Gebruikersinstellingen';
 ?>