view .tonioni @ 1362:d79e21855aef

Add mechanism for saving/loading colour maps by name/id rather than by numerical index, for future compatibility when adding to or changing the supported colour maps. Add two new colour maps (and one old one). Write out backward-compatible numerical indices for use when reloading in older versions. Also add a mechanism to invert the colour map, though I don't think it turns out useful enough to include in the UI.