Color Scheme Creator: Create a color scheme from a base color

This class can be used to create a color scheme from a base color.

It takes a base color and creates a list of derived colors that consists of several lighter and darker variants of the base color.

The class returns an associative array with generated color values in RGB with entry names prefixed with the original color name.

The array also returns HTML image tags to display the colors in a Web page using transparent images with the background color set to the generated color values.