On the current front page at https://www.staging.scheme.org/ there's a
"Topics" section featuring subdomains matching the topics we founded
mailing lists for: Communications, Persistence, Testing, Web development.

IMHO these have not had the level of traction (in the sense of work done
per unit of time) to warrant such a prominent place on the site.

I suggest we instead start a "groups" subdomain where anyone can start a
workgroup on some topic and put up static files for it. So the URLs
would be something like this:

group.scheme.org/comm
group.scheme.org/persist
group.scheme.org/test
group.scheme.org/web

group.scheme.org/objects
group.scheme.org/types
group.scheme.org/pre-srfi
group.scheme.org/...

In theory we could also give a nested subdomain to each group:

    comm.group.scheme.org
persist.group.scheme.org
    test.group.scheme.org
     web.group.scheme.org

The idea would be to have a low barrier to entry, so if someone wants to
post docs or notes on some topic, they can just do it. A lot of good
Scheme notes are currently scattered around the net where it's hard to find.

The current "Topics" has one site per topic, but if the groups are lower
effort and less prominent, we could let people make more than one group
per topic to explore alternatives.

How to upload files to a group? I suggest we start out with rsync and
then figure out something better.