[TME] Add TurnModify effect pipeline #41
Description
Description
In current STK, there is SpeedIncrease, and there is SpeedDecrease. These two create effects that modify engine power and top speed. There should also be TurnModify effects, allowing to multiply or even assign piecewise linear modifications to turning dynamically. The first mechanics to make use of it could be a modification to the electroshield that reduces turning, and in kart_characteristics.xml, assigning turning modifiers to both the startup bonuses and the skid releases bonuses.