bug#63875: 26.3; Doc of `dired-guess-shell-alist-user'

[Drew Adams <drew.adams@oracle.com>]

> > But it would be good, I think, to add that it's
> > not just about shell commands.  Some users will
> > not recognize that they can invoke executable
> > programs this way.
> 
> Shell commands are a super-set of executable programs, so I see no
> reason to change anything here.  The variable is used to invoke
> commands via a shell, so "shell command" is exactly right.

Yes, but many Emacs users won't know that.

Unless they're programmers or they are used to
GNU or Unix or Linux, some users won't guess
that they can use this user option to associate
applications (executable binaries) with file
names for Emacs.

MS Windows, for example, may know how to create
default file associations for programs invoked
normally (for Windows), but Emacs users on
Windows might well not guess that they can
associate files with programs for Emacs.

If you disagree that this is the case, fine.
But if you agree then maybe you'll consider
explicitly mentioning this use of the option.