updated readme to include license statement

Author: zhigenzhao

README.md

@@ -82,4 +82,7 @@ Robotics Simulation and Solver
 
 Hardware Control
 - [`dynamixel_sdk`](https://github.com/ROBOTIS-GIT/DynamixelSDK.git): Dynamixel control functions, Apache-2.0 License
-- [`ur_rtde`](https://gitlab.com/sdurobotics/ur_rtde): interface for controlling and receiving data from a UR robot, MIT License
+- [`ur_rtde`](https://gitlab.com/sdurobotics/ur_rtde): interface for controlling and receiving data from a UR robot, MIT License
+
+## License
+This project is licensed under the MIT License - see the [LICENSE](LICENSE) file for details.