Bug#744865: Add check and warning for unetbootin

[Brian Potkin <claremont102@gmail.com>]

On Tue 15 Apr 2014 at 16:46:30 +0100, Steve McIntyre wrote:

> As suggested in #739767...
> 
> unetbootin used to be a helpful tool for many people to create
> USB-bootable installer images, but these days seems responsible for
> lots of user problems and difficult-to-resolve bug reports.
> 
> If feasible, check to see if we were booted from unetbootin media. If
> so, print a big warning to the user that unetbootin is potentially
> problematic and not supported. (Maybe) let them continue after
> acknowledging the warning anyway(?), but be sure to log the warning in
> the syslog for the benefit of d-i developers.

I'm not particularly fond myself of advocating unetbootin to put an
image on a USB stick but wouldn't something in the CD FAQ also be
helpful. For example:

   https://lists.debian.org/debian-www/2012/08/msg00053.html

and

   https://lists.debian.org/debian-www/2012/08/msg00053.html

Writing to a CD gets some prominence, in spite of the defects it
contains:

   https://lists.debian.org/debian-www/2012/09/msg00049.html

All of which need reviewing. And all of which may be totally useless :).

I don't think we should be supporting anything which is not in the
Installation Guide. Picking out one program for Debian's approbation
seems a little extreme.

Regards,

Brian.