optimize UX

src/views/DE/404.pug

@@ -26,5 +26,6 @@ html(lang="de")
         br
         br
         p(class="h5") 404. The requested URL was not found.
+        p <a href="./">go back home</a>
     // Bootstrap
     script(src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM" crossorigin="anonymous")
\ No newline at end of file

src/views/DE/500.pug

@@ -25,6 +25,7 @@ html(lang="de")
           img(src="https://transfer.hft-stuttgart.de/img/M4_LAB_LOGO.jpg", class="img-responsive center-block", width="185", height="192")
         br
         br
+        p <a href="./">go back home</a>
         p(class="h5") 500. Unexpected Error :(
         p #{ error }
     // Bootstrap