caution: new website 24-hour test

[Graham Percival]

We’re testing our new website! For the next 24 hours, the new website
will be the default website; after that, we will switch back to the
old website while we examine feedback and make improvements to the new
website.

There's some issues with translations, in particular with links to the
manuals.  Some translations work; others don't.  If somebody who cared
could take a look at them and fix the broken ones, that would be nice.

CAUTION: as we agreed after much discussion in the past, the new
website is generated automatically from git master.  So if you're
screwing around with Documentation/web/ or any of the translations,
know that whatever you push will be seen within 1-2 hours.  So don't
push anything that you haven't tested.

Cheers,
- Graham