Show version information in dot graph

This is a very useful command `stack dot --external | dot -Tpng -o wreq.png` from https://docs.haskellstack.org/en/stable/dependency_visualization/

It would be nice to have another flag to show the version numbers of each package. And also to color the circles green if it's the latest version and red when it's an old version. When multiple packages require the same package but different versions the arrows to that package can be colored differently.