Create a colormap 'import' function

[Mangara]

This takes a list of colors and finds the best fitting colormap in our model.

[Mangara]

Implementation ideas:

• Given color points and order, fit spline to this
• Points define a curve in LAB space
• Preprocess this to get a curve with monotonic lightness: longest increasing subsequence?
• Have a method that, given the points and a number of control points, finds the best quadratic spline to approximate these points
• Binary search for the spline with the smallest number of control points that has reasonable error