Bug#744865: Add check and warning for unetbootin

[Brian Potkin <claremont102@gmail.com>]

On Wed 23 Apr 2014 at 15:37:56 +0100, Steve McIntyre wrote:

> ACK. I'm going to look into that lot again myself.

Thanks. I may have gone over the top with a few things like reorganising
some things on the page. If I were doing it again today I'd be inclined
to pare it down somewhat.

> In my experience it's far and away the most common (external) cause of
> problems in the installer. I've just responded personally to yet
> another user who seems to have bitten by it.

If you hadn't I would have. Personally, I find it annoying given the
surefire method of writing to a USB device is featured so prominently
in the documentation for Linux users at least.

Regards,

Brian.