[ROS] Add Official Docker image for ROS2 (#1381)

* docs for ROS 2

* Update example dockerfile and compose file

* Add minimal ros1_bridge example

* Fix logging for python node
https://tarunlalwani.com/post/why-delayed-output-python-docker/

* Link external license resources like other images
https://github.com/docker-library/docs/blob/master/ubuntu/license.md