Once the car is going a certain speed, some doors should auto-close. That speed could be the same speed as when the brakes auto-apply in simple throttle mode.

This would have to be a true/false because we wouldn't want windows/convertibles to auto-close!

I would prefer to have this another way than speed-based due to player confusion. Any alternate thoughts?

Did this in commit 0c52bb0. Forgot to reference issue number.

Implemented in V19.9.0.