Roomba 真空机器人方形椅子腿塞

A simple stopper for square chair legs, so a robot vacuum like the iRobot Roomba does not get stuck on top of the legs. Can probably be used for other furniture.
Veion 2, that is included in this thing, was done by TheFisherOne, to make the code more friendly for the customizer, and fixed rendering issues. Thanks alot!