Suggestion: Add value at which damage takes effect

[mlewelt]

Currently even the smallest damage a vehicle has will reduce yield / horsepower etc. (see wear factor thread). My suggestion is to add a customizable value which sets at which point the damage a vehicle has takes actual effect on yield etc. So as an example setting the value to 50% would mean that a 45% damaged combine doesnt get reduced yield, only when it hits 50% the effects will kick in. Implementing this should be easy: Override vehicle.getVehicleDamage() function and return 0 when damage is below setting and return the value from super when damage is above setting.