Method get_grove_analog

Software/C/GoPiGo3.cpp:655–659

}

uint16_t GoPiGo3::get_grove_analog(uint8_t pin){
  uint16_t value;
  get_grove_analog(pin, value);
  return value;
}

int GoPiGo3::get_grove_analog(uint8_t pin, uint16_t &value){
  value = 0;