docs/189901: Update the jail section of the handbook

[bcr at FreeBSD.org]

Synopsis: Update the jail section of the handbook

Responsible-Changed-From-To: freebsd-doc->bcr 
Responsible-Changed-By: bcr
Responsible-Changed-When: Sat May 17 23:40:49 UTC 2014
Responsible-Changed-Why: 
Assign this to me as it was created as part of the Doc Lounge at BSDCan 2014.

http://www.freebsd.org/cgi/query-pr.cgi?pr=189901