Update README.md with correct example script (#67)

* Update README.md with correct example script
* Also update sphinx doc

Author: urfeex

README.md

@@ -98,7 +98,7 @@ ros2 launch ur_simulation_gz ur_sim_control.launch.py
 
 Move robot using test script from  `ur_robot_driver` package (if you've installed that one):
 ```
-ros2 launch ur_robot_driver test_joint_trajectory_controller.launch.py
+ros2 run ur_robot_driver example_move.py
 ```
 
 Example using MoveIt with simulated robot:

ur_simulation_gz/doc/usage.rst

@@ -21,7 +21,7 @@ Which can be tested by using a test script from ``ur_robot_driver`` (if installe
 
 .. code-block:: console
 
-   $ ros2 launch ur_robot_driver test_joint_trajectory_controller.launch.py
+   $ ros2 run ur_robot_driver example_move.py
 
 If we also want to be able to use MoveIt!, then: