#4 coloring options

[Elmar de Koning]

provide options to / or automatically perform:
1. fill a single closed line
2. change color after each n lines
3. change color for each branch level
4. provide a color set
5. use complete random colors
6. special tree coloring:
first n depths are brown, all depths > n are green. Maybe even specify a starting green and end ending green color

see http://ejad.best.vwh.net/java/fractals/lsystems.shtml for some strinking examples, especially tree 3 looks awsome.