Remove obsolete JS libraries

The new gallery doesn't use the jQuery mousewheel and hashchange events so we're dropping those.
Since those were the only pieces of code depending on jQuery we can drop that dependency too.

Author: Sander De la Marche

_layouts/default.html

@@ -35,6 +35,5 @@
             <a href="/impress.html">Impressum</a>,
             <a href="https://github.com/i3/i3.github.io">Source</a>
         </footer>
-        <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
     </body>
 </html>

js/gallery.js

@@ -1,4 +1,4 @@
-// Vanilla JS basic gallery - use at you please
+// Vanilla JS basic gallery - use as you please
 // © 2020 Sander De la Marche
 
 const screens = [];