Experiment with matplotlib's triangulation.
Matplotlib triangulation with refined isometric coloring.
Use real weather data for image.
Include airTemperature in aggregation output.
Hack up a GroundOverlay class and use it with a screenshot image.

fastkml doesn't include it for some reason. Since fastkml does isinstance checks, either
GroundOverlay needs to inherit from Placemark, or we must update fastkml.