Add a class to better manage iocage jail.conf files
When we shifted responsibility of handling jail ip's to jail(8) in iocage, we also shifted other responsibility to jail(8) like exec_prestop. Now iocage also executes this and jail(8) does as well. We should change this behaviour and make sure these tasks are executed only once. It should be investigated what's the best approach here maintaining the configuration knobs we have for these tasks.
We risk breaking exec* services
It should be confirmed that exec_prestop/prestart etc are executed only once