Enchantment work

-Placing an item in the enchantment table now displays 3 levels in the enchantment GUI (they cannot be clicked or interacted with in any form at the moment)
-All items have been given an "enchantability" level instead of using an Enchantable interface. This allows plugins to easily allow items that normally would not be enchantable to be enchantable. Items with an enchantability of 0 (default) cannot be placed in the enchantment table inventory slot. Enchantability is used in the process of calculating enchantments for an item (also not started yet).