add some elements to mobile, prioritize order

* add table tennis to mobile as well
* add public toilet to mobile, prioritize order of elements a bit

@homtec can we combine the mobile and desktop list into one by the way?

In general it seems that we should do the mobile/desktop distinction via media queries only. Actually the mobile site works on desktop quite well, especially because the »the next […] is« is in one line. The social media and other notes could just go on the right, and vanish on mobile behind a dropdown.