this should not change their behaviour with "nix run", which was
the reason for putting them there in the first place (however, it does
remove the ability to build them with "nix build", but afaik this has
never been used by anyone).
This means the packages.* output is now left unused, so we can use it
instead for things that actually are programs which want to expose
(see the next commit after this one for an example).
however, for some reason, ACME still fails. Hopefully it's just the
rate limit, but it does look suspicious; there' still a
"www.muc.hacc.space" in the log that oughtn't be there …
