add dutch translation for PHP8 splash page (#3)

* add dutch translation for PHP8 splash page

* fix some typos and reword some things

Co-authored-by: Roman Pronskiy <root@pronskiy.com>

Author: 2 people

include/layout.inc

@@ -710,6 +710,7 @@ function release_language_chooser($currentlang) {
     $LANGUAGES = array(
         'en'    => 'English',
         'pt_BR' => 'Brazilian Portuguese',
+        'nl'    => 'Dutch',
         'ru'    => 'Russian',
     );