PWA / Offline Support

[L1lith]

I know this is kinda niche but it would be cool if we made the website work offline for people who don't have access to a reliable internet connection. This would also probably mean we'd need to have a settings page about which languages to download and a service worker capable of only caching translations as configured by the user.

[obiot]

funnily the latest version of the documentation now has a setting page where it's possible to enable an offline version of the page through a service worker :)