Changes summary:
- fixed rotor displacement
- motors are more paintable
- reduced collision boxes

Changes details:
- rotor displacement now defaults to 0, which also happens to be the new 'true zero'
- rotor displacement is now between -25cm and +25cm for Large version, -12.5cm and +12.5cm for Small version, in order to match other motor mods and allow better multi-motor alignment
- stators texture mapping updated, matching paintability of vanilla motors
- collision boxes are no longer bigger than vanilla ones, for compatibility purposes