Gripper control

<!-- initialize the program -->
const mycobot = require('mycobot')

const obj = mycobot.connect('COM15',115200)

<!-- set the open and closed states of the gripper mycobot.setGripperState(open and closed states , running speed)-->
<!-- Note: reference values for open and closed states:0-open, 1-closed, and running speed is limited to 0-100 -->
obj.write(mycobot.setGripperState(0,10))

<!-- set the angle of the gripper mycobot.setGripperValue(angle value, speed)-->
<!-- Note: the angle and speed values are limited to 0-100 -->
obj.write(mycobot.setGripperValue(80,20)))