New jail(8) committed

[Mr Dandy]

Looks like the new functionality lost abilities of old /etc/rc.d/jail to carry 
out multiple quantity of prestart/stop instruction

Old cool feature:
jail_example_exec_afterstart0=""
jail_example_exec_afterstart1=""
..

In new style it doesn't work:
exec.start0 = '/bin/date';
exec.start1 = '/bin/date';
..

also it would be great to have "include <config>" for some other places
(/etc/jail.d for example) that it was possible to have one config per jail.