[Feature] - Add option in config to automatically save plot worlds in a seperate folder

[LordTuxn]

Bukkit has a feature, to change the directory for worlds. This is editable in the Bukkit.yml file by adding settings.world-container: plots Advantages: More manageable and cleaner, especially with a large number of worlds.

This feature should be configurable in the config.yml. It should also move all existing worlds to the new directory.