Roll out "gap in the browser" more officially? #6593

Few people will currently know about the work by @ChrisJefferson that allows using GAP in a browser:

https://gap-system.github.io/gap-in-the-browser/

Sources: https://github.com/gap-system/gap-in-the-browser

It'd be nice to have this become a bit more official. Some ideas:

1. hosted it e.g. https://try.gap-system.org (not hard, I can take care of that)
2. change it to use a GAP release version (presumably doable once GAP 4.17.0 is out)
3. whenever a new GAP release is made, update the webassembly version (so an automation task)
4. have this linked from the GAP front page prominently
5. maybe integrate it more with the main website's layout