Updating dired-guess-shell-alist-default

["Philip K." <philip@warpmail.net>]

Hi,

I wonder if anyone else shares my point of view: while useful,
dired-do-shell-command seems somewhat outdated. Certain file formats
haven't changed much, and their handling is still ok (.patch, .tar.*,
.sig) but especially image, video files and documents suggest tools
that don't seem to be installed by default on most systems (xloadimage,
xpdf, ...).

Of course this can be mitigated by using dired-guess-shell-alist-user,
but I think that this shouldn't be necessary. I usually just map all
images, videos and documents to xdg-open, and changing the values to
something like this wouldn't be bad a bad idea, if you ask me
(especially because xdg-open doesn't block).

So if not xdg-open (at least on GNU/Linux and other XDG-compliant
systems), should the default value be changed to something that makes
dired-do-shell-command more useful, out of the box?

-- 
	Philip K.