I made it possible for the config to store different metadatas of the items.
Since the metadatas used for getting things like red wool or lapis lazuli are the same as the durability used in things like swords or axes, I made the option to default. In this case it will disregard the durability and only do the price of whatever is at your 0th durability state.
As well added error codes.
Note: If you do not set a price for a particular durability and you do not disable the useDurability...