Worked on jail functionality

This commit fixes several bugs:
- The makefile didn't install the last two jail.sh.* files
- The zfs_getfs is used has has to return nothing (not a warning)
- The jail.sh update_jail option was missing an argument
- The jail.sh.dragonfly had a few things that needed to be fixed

TO-DO: The jail_runs check is again not acting correctly and I'm wondering
if it is even worth having.  It's not under an actual jail, so the jail
status would have to be monitored to do this correctly.  I need to mull
this over.