Skill use

make it where you can use any lvl of a Skill you choose to use, say you are a wizard and have lvl 10 of Pyro. and want to cast lvl 4 you can just choose to cast it.

however all lvls of a skill should be on the same cool down, example: you can not cast lvl9 Sand and then lvl10 Sand, because it would still be on cool down from casting the lvl9 Sand.