invertTheta() method added, now time for some questions

I added the method that will "invert" the angles whenever a call is placed to move() a servo. I believe this part of the algorithm works, but I'm having a lot of trouble getting the calibrate method to do anything that resembles calibration--I either have something wrong, or something was wrong with this method before I got to it. 

Rather than just merging this immediately, can you have a look and see if I've missed a spot where the angles should be getting transformed?

Let me know what you think. I'd really rather attach the notion of "counter-clockwise" to the Servo object within johnny-five, but I'm not sure how to do that. It's tough to know whether or not my desire to alter Servo is just my Java-nature coming through while I work on this code...
MM