Create arm motor controller class

[EricCrosson]

Parameters:

• ranges min pwm
• ranges max pwm
• pwm output pin(s)

Functions:

• move to angle(angle)

  determine pwm output to accomplish movement to desired angle

Not sure if necessary:

• linear interpolation

[stormymauldin]

I'm pretty sure most of our servos have a range of 2π radians.
I'm not sure if this has been decided yet, but are we using a 0 to 2π range or a +/- π range?

[EricCrosson]

From the docs, we are given a min angle and a max angle
I think our IK library will work with angles, so we need to ensure we can dump an angle into this library to start the desired movement. Absolute angles is the answer, I think those are normally mapped from 0 to 2 pi. I don't believe we can hit the entire range though.