Documentation restyle and re-organization

[bconway]

Geolocation Server has gone away as an independent service:

[release] ChirpStack Application Server v3.11

ChirpStack Application Server v3.11.0 Features OpenID Connect authentication This feature makes it possible to use an OpenID Connect authentication backend together with ChirpStack Application Server, for example Auth0.com. Users are automatically matched based on email address on the first login. If there is a successful match, an external OpenID Connect user identifier is associated with the user, so that even in case of an email address update, it can still be matched (and updated in the Chir…

I suppose that doesn’t help people still running it, though.