Minor modifications to Servo.h
 Undo a58eef removal of NUM_NONCONT_SERVOS (having a constant is cleaner, and doesn't require a calculation everytime servoSetAngle is called
 Make servoDefinitions static to avoid modification by included files
Add skeleton Joystick.h library
  Contains enums for referring to joystick buttons
Add max power array to Motor.h
  Implements and fixes issue #13 by using array[tMotor]