docs/156853: [patch] Update docs: jail(8) security issues with world-readable jail root

[bcr at FreeBSD.org]

Synopsis: [patch] Update docs: jail(8) security issues with world-readable jail root

Responsible-Changed-From-To: bcr->freebsd-doc
Responsible-Changed-By: bcr
Responsible-Changed-When: Mon May 7 11:50:43 UTC 2012
Responsible-Changed-Why: 
Drop this back into the pool, as I could not make much progress on it.
The last discussion points revolved around the question whether jails are
meant to be a security feature or for virtualization purposes. Maybe someone
else can find a better solution, I'm not even sure that doc is the right
category for this PR at the moment.

http://www.freebsd.org/cgi/query-pr.cgi?pr=156853