Improve responsive design (search form, table) and menu button

* Search form: invert position of search field and search options, improve design on small resolutions (especially under 480px).
* Tables: display labels when table items are collapsed (if class="collapsable"), don't collapse tables without specific class
* Menu tile: center Transvision title, move menu to the right and use a smaller image for large resolutions (125x75 vs 150x90) and a tiny one for under 480px (100x60px) to avoid overlapping
* Add extra padding on credits and changelog, fix typos in changelog, add new/exp tags for new/experimental features

This should fix issue #164 and probably issue #86