bug#69305: outline-minor-mode for tabulated-list-mode

[Eli Zaretskii]

> From: Ihor Radchenko <yantar92@posteo.net>
> Cc: Eli Zaretskii <eliz@gnu.org>, 69305@debbugs.gnu.org
> Date: Sat, 24 Feb 2024 18:06:46 +0000
> 
> I am wondering if flexible grouping system from Adam's org-super-agenda
> package may provide some inspiration.
> Check out
> https://github.com/alphapapa/org-super-agenda/?tab=readme-ov-file#usage

What I had in mind was much simpler to use.  But I guess I'm the only
one who wants to let users set up grouping in some easy way, because
I'm being shown more and more complicated customizations, claiming
they are suitable.