Adding this package with the necessary dependencies makes sure that if it's
installed its dependencies are installed as well and everything should work.
Archlinux doesn't specify a value for this and relies on applications knowing
the default. Guix adds values to this list, meaning that because there is no
value initially it overrides the defaults completely. One thing that always goes
wrong when this happens is that Firefox installed through ‘pacman’ won't be able
to find some schemas it needs to show the upload file dialog and crashes when I
try.
The herbstluftwm configuration isn't complete yet, it's only the package so far,
but it does extend the xsession service to include a line in xsession to execute
the window manager in a bit of a hacky way.
This also adds a ‘mixed-executable-file’ function which is the same as the
‘mixed-text-file’ except that it also sets the executable bit for the computed
file.
