ROS 2 version

[ashBabu]

Hi,
Thanks for your work.
I have made a ROS 2 version of your code and is available at simple_loop_closure.
Currently it is configured to run DLIO and the Readme pretty much explain the changes. Have not done extensive tests and hence there could be some mistakes.

Just for information in case anyone needs it
Thanks

[kamibukuro5656]

Sorry for not reacting for so long.
Thank you for your excellent work.
I have added a link to your repository to the README.