Data Attributes

+Added multiplier based attribute functions.

Why: among other things such as being a requested enhancement, flat Attack Speed buffs are too OP and really need a multiplier type mechanic.

How: when defining attribute functions in JSON, instead of the value being a number/double, it is an object containing aforementioned number as well as a FunctionBehaviour reference. This lets the game know how the value should be used.

This is a breaking change, hence the buff in middle version number. All mods/datapacks will need to adjust their data JSON accordingly.