Renaming stumpwm contributor packages

[Katherine Cox-Buday]

StumpWM is a window manager which has optional, community contributed,
modules you can use. I went to go add these to Guix and discovered
they're already present albeit with confusing names.

For example, `sbcl-stumpwm-pass` is simply `sbcl-pass`. This limits
discoverability, and suggests that these packages are more broadly
useful than they are (as far as I know they are only useful within the
context of StumpWM).

Can I get a +1 from someone appropriate to rename these packages to be
prepended with `sbcl-stumpwm-`?

-
Katherine