Let's see if these patches get accepted now! I think I've taken into 
account
every single detail.

These patches add three packages: vis, lua and libtermkey. vis depends 
on lua
and libtermkey, so add them before adding vis.

vis is being added in a new file, gnu/text-editors.scm , as requested 
here
<https://lists.gnu.org/archive/html/guix-devel/2016-12/msg00242.html>

-- 
José Miguel Sánchez García