Support color by name
Store colors in the current context
Independant `stroke` and `fill` color
Larger image for shape tests
Changed the `draw` function name to `display`.

This would reduce confusion with the Java `draw` method
which is basically `stroke`
Support for multiple shapes display
Preliminary version of drawing mini-language
Support for setting fill color in the mini-language
Path specifications mini-language
Add test to check for path interior filling
Add support for cubic Bezier curves in path
Support for translations