Create a Configuration Assistant Analog to MoveIt

[SteveMacenski]

Moveit has long has a QT configuration assistant. MoveIt also has a bunch more auto-generated files required to work and more complex things to describe with kinematic chains than we do so that has made sense.

However, having some configuration assistant could be extremely beneficial to get users on their way with minimum friction. I don't know if we'll be able to cover every single parameter, but we should be able to cover the broad strokes with the costmap, how to layer them, select a URDF and frames making sure they comply with standards, planner, perhaps controller through the Qt GUI and show how the parameters effect the robot, etc

[SteveMacenski]

While we may come back to this in the distant future, we have now a complete first time robot setup guide with explanations, images, and examples https://navigation.ros.org/setup_guides/index.html. While that doesn't quite meet this need, it does provide instruction to help a user setup Nav2 for the first time with graphical examples.

Closing this since unlike moveit, we could not meaningfully display graphically all of the parameterizations needed for a first time setup with Nav2 (e.g. AMCL params or DWB sampling params) and would mostly be useful for setting up the costmaps, which will shortly have dynamically reconfigurable parameters again #956

If someone is interested in working on this, I'd love to brainstorm and make it happen, but for now I think we're going to drop this from the long term roadmap.