added "command-blacklisting" flag that allows players to blacklist commands in their own fields (http://wiki.sacredlabyrinth.net/index.php/Field_Flag_Reference#command-blacklisting)
added /ps blacklistcommand [command] - blacklist a command
added /ps blacklistcommand clear - clear the blacklist
added "fence-on-place" flag that will generate a fence around a newly placed field (http://wiki.sacredlabyrinth.net/index.php/Field_Flag_Reference#fence-on-place)
added "price-per-fence" flag to charge per fence piece generated (http://wiki.sacredlabyrinth.net/index.php/Field_Flag_Reference#price-per-fence)
added "settings.fence-max-depth" to config to set the maximum depth of the fence