Color Palettes for Ordinal Categories

[jstcki]

As described in https://github.com/visualize-admin/visualization-tool/issues/101#issuecomment-973001152, we should offer sequential color palettes for ordinal dimensions.

Not sure if the selection has to be strictly limited to ordinal dimensions, as they may also work for dimensions that are sorted manually.

For reference, d3 offers these single- and multi-hue palettes out of the box: https://observablehq.com/@d3/color-schemes?collection=@d3/d3-scale-chromatic