Since we don't want to come up with a GUI maintenance system and
instead focus on the steering behaviors, all relevant variables have
been moved as exported in the main demo script for each toy.
Changed text boxes to sliders to improve usability. This also involved
adding some simple graphics, since the _draw method is not
anti-aliased and doesn't look great.
The use of multiline blocks in GDSCript for comments leaves them in the
final compiled file, increasing size and potentially processing for no
end-user gain.
