Add root drive mapping to default config file

[Mike Hearn]

> In that case, the root mapping meant things 
> got out.

IIRC the virus was your typical Outlook email worm, which doesn't even
need temporary files as far as I know, let alone a large read only drive
full of stuff it doesn't understand. Whether root is mapped or not would
make little difference to those kind of things.

> Mapping the root is a bad security decision, even if we don't see the 
> exact attack vector at the moment.

The most interesting stuff for hackers/virus writers is almost always in
the home directory, which is mapped by default. So, I think people
overrate the importance of the rest of the system files here.

-- 
Mike Hearn <m.hearn at signal.qinetiq.com>
QinetiQ - Malvern Technology Center