[feature request] namespace grouping on the graphs

[Valqari-Engineer-I]

Congrats for this project, it is really useful for anything ROS2.
The main difference that I saw in this tool compared to rqt_graph is that ros2_graph does not perform namespace grouping. Not sure why but if it could be added that would be nice.
Here is an example image of how does it look in rqt_graph

Thank you

[charlielito]

Thanks @Ivan-ValDev ! That is indeed a very nice feature we'll implement