be explicit about installing packages from universe in getting-set-up

[Allison Randal]

Several packages the reader is instructed to install in the getting-set-up article are in universe, rather than main. For new developers, this can be confusing as they get errors about packages not existing. The article should provide a brief pointer on how to enable universe.

[Daniel Holbach (dholbach)]

AFAIK Universe is enabled by default since quite a long time now: https://wiki.ubuntu.com/AlwaysEnableUniverseMultiverse

[Allison Randal (allison)]

Not in a debootstrapped chroot. It doesn't need a big mention, just the equivalent of a small footnote, to keep newbies from getting stuck.

[Daniel Holbach (dholbach)]

Ah ok, that makes sense. It'd be ideal if the package containing setup-packaging-environment was in main and deal with all of that, but in the absence of it, we should document it. Agreed.