devfs_ruleset shoudl be configurable
Created by: kevinmeziere
devfs_ruleset referes to a rule in the file /etc/defaults/devfs.rules. While ruleset 4 works it is only a sample default shipped with freebsd. More sophisticated users than us will likely have their own ruleset so we should allow them to set it. A system wide config would be better than a default, a per vm setting would be better, especially if we want to grant certain vms more rights for example a particular device (gpu) in the future.