bug#56510: Make some games obsolete (or just remove them from the menu)

[Po Lu via "Bug reports for GNU Emacs, the Swiss army knife of text editors" <bug-gnu-emacs@gnu.org>]

Stefan Kangas <stefan@marxist.se> writes:

> Some of the games in Emacs look a bit dated.  I put it to you that they
> are not excellent promotion for Emacs, and that we are better served by
> having fewer but better games.
>
> I suggest that we either remove some of them from the "Tools -> Games"
> menu, or obsolete them outright.  Here are the ones that I don't think
> pass the bar:
>
>  - 5x5.el
>  - blackbox.el
>  - gomoku.el
>  - pong.el
>  - solitaire.el

I especially oppose obsoleting Le Solitaire, Pong, and Blackbox.  As for
the others, I think there's no point in ever declaring an amusement
obsolete, especially since we haven't been getting any more lately.

As for the menu, removing it seems to be a no-brainer, since games are
not tools.