#75 A better Reindex Colormap dialog

[harbinger]

When this dialog is open, i would like to select a start hue and finish hue, re-sort those colors based on the difference of value, saturation, or RGB components, and then do the same for any other paris of hues. I have many colormaps which go from black to white with one series of colors, then low-saturation to high saturation in another band. I want to be able to keep the bands separate. Perhaps the indexing can happen vertically AND horizontally. Furthermore, i'm having trouble making out the colors with the small boxes and white background. Perhaps the dialog should display bigger swatches and put the number inside the respective swatch.