bug#21612: 24.5; Configuration variable to delete auto-save file when intentionally killing buffer

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: monnier@iro.umontreal.ca,  mrok4a@gmail.com,  21612@debbugs.gnu.org,
>   rms@gnu.org
> Date: Mon, 23 Aug 2021 15:58:54 +0200
> 
> >> The two things (deleting auto-save file when saving a file and killing a
> >> buffer) do not seem to be very related functionality, so having one
> >> variable for both things is just confusing.
> >
> > We could have 2 variables, yes.
> 
> ... so I've pushed the two-variable solution now.

Hmm... bother.  If the new variable kill-buffer-delete-auto-save-files
is non-nil, we ask the user even if we eventually don't delete the
auto-save file, for example if auto-save-visited-mode is in effect.
Is that TRT?

Also, I'd bet people would like to be able to delete them without any
questions asked, so maybe the variable should be a tristate, not a
boolean?

Thanks.