Essentially using a naive threaded solution with a naive escape
routine for choosing whether a given location is actually in the
Mandelbrot set. I think the colouring solution is quite unique: I use
a scaled quadratic function which ensures maximum colouring is given
to those with medium number of iterations. I'll try a linear ratio
next. Currently we start properly lagging at ~2^20 iterations, which
is why I'm looking for a better way to draw and compute escapes.
