Allow individual flags to handle the flag command
New inventory system - Each world has an inventories.yml file that is used as a data storage file for regions with the inventory flag
Inventory flag ~ Regions can now have unique or pre-defined (kit) inventories. Player inventory is saved and cleared before entering the region, and returned on region exit.
This currently crashes the server, so don't use until [this](https://github.com/DenizenScript/Denizen-For-Bukkit/issues/912) is resolved.