Crate Tag or Branch for ROS2 Users

[harderthan]

Hello. First of all, thanks for this package.

I'm following aws-deepracer tutorial.
They provided the guide with ros2 package included rf2o_laser_odometry package to handle the deepracer robot.
But, someone who want to know this package couldn't find ros2 branch on main page of this repository, because there is no tag and branch for ros2. They can only find the commit through the script.

Could you crate tag or branch for ros2 user?
This(#29) is suitable commit for this issue.