Make rotating bed more rigid

[seanngpack]

Describe what was wrong with previous design/areas of improvement When you rotate the bed by hand it has a little bit of give. I think it may be caused by the stepper motor mount flexing. The mount is secured using only two points so that may be the culprit.

Describe the solution you'd like Redesign the motor mount to have more support from bending and also add a third mounting point.