[ROS2] Existing options for hiding/showing parameter related topics needs to be updated

[wjwwood]

In general the settings in rqt_graph that are for showing/hiding topics related to debug, parameters, command-line tools, etc. need to be revisited.

Just walking through this tutorial (https://wiki.ros.org/ROS/Tutorials/UnderstandingTopics) and emulating the use of rqt_graph you can see that some of the steps which show you how the command-line tools show up do not work correctly and there are some topics that are related to parameters which are always shown and just cluttered the example. So there probably needs to be an option to hide parameter related topics, or maybe it should be included under "debug" or maybe the parameter events topic should be hidden (have a _ added to the beginning of the name). I'm not sure. But as it is it's a bit annoying when trying to show simple examples in the tutorial mentioned above.