Updated doco, updated code to match gravjac method and pay inputs.
Updated doco, updated code to match gravjac method and pay inputs.

jaejunlee0538/robotics-toolbox-matlab,konradb3/robotics-toolbox-matlab,yasha0b1/robotics-toolbox-matlab,konradb3/robotics-toolbox-matlab,yasha0b1/robotics-toolbox-matlab,yasha0b1/robotics-toolbox-matlab,jaejunlee0538/robotics-toolbox-matlab,jaejunlee0538/robotics-toolbox-matlab,yasha0b1/robotics-toolbox-matlab,konradb3/robotics-toolbox-matlab,konradb3/robotics-toolbox-matlab,jaejunlee0538/robotics-toolbox-matlab,konradb3/robotics-toolbox-matlab,jaejunlee0538/robotics-toolbox-matlab,yasha0b1/robotics-toolbox-matlab