[Feature Request] Move Manufacturer class out from under motor

[JoePfeiffer]

The Manufacturer class was originally created to be specific to motor manufacturers, so it is in the motor package. At some point it also started being used for manufacturers of other components, and at this point has at least two manufacturers that don't even manufacture motors. The motor type member should be removed (I'm not sure why that was relevant even when it was only motor manufacturers), and the class moved somewhere else (not quite sure where).

This is not urgent as the change would be completely transparent to users, but would be a little bit of code cleanup.