Split Scale attribute between horizontal and vertical.

As the title says, the scale attribute should be split between a horizontal (length & width of an entity) scale and a vertical (height of an entity) scale. This would be useful in developing datapacks as "custom" mobs could have their hurt box changed in one of the directions without having to change the hurt box in the opposite direction (ie: something using a zombie as a base but ideally with a cube hurt box). Additionally, the non-technical community would probably get a kick out of it for a day.