Controller interface component node for servo (xbox)

[tylerjw]

The xbox controller interface already exists here: https://github.com/ros-planning/moveit2/blob/main/moveit_ros/moveit_servo/src/teleop_demo/joystick_servo_example.cpp

I would like an image like this one showing what each button (and joystick) does:

This should go in a tutorial for how you use moveit_servo with this controller. An example launchfile that opens rviz with the panda in simulation using this controller should be included.

[henrygerardmoore]

Adding the tutorial in this PR. The launch file doing what you wanted already existed, just had to make the image and the tutorial (explained the launch file and the node a little).