Adapt "unknown command" message to current CraftBukkit implementation.
[CONFIG] Command protection: Change config sections + change to lists.

Commands to change to "no permission" or "unknown command" behavior,
can now be configured with a string list each. Commands that have a 
permission set will have the default set to false, while commands that
don't have a permission will be altered to have a filter permission,
namely nocheatplus.filter.command.<commandname>.