Only one Sorsel

[gennyble]

Combine HeuristicSorsel (introduced in 8ed590a) and SelectSort into Sorsel. If max_attempts is 1 then we do it like SelectSort without even calculating the score ( we don;t need it). Otherwise to the guess-and-check. is it gradient descent? A butchered version, maybe.

also:

• I'd love to see how the score varies with the tolerances. So I will make a graph of every 0.1 step in tolerance from 0 to 100. tolerance on X axis, Y is the score and maybe also one for colors selected. I think there are local extrema and I'd love to get an idea on howto avoid them.