Measure performance of d3-voronoi and d3-geo-voronoi.
It looks like d3-geo-voronoi is O(n^2), on my computer I have
time (in ms) ≈ 40 * 1e-6 * n^2
n = 100, 0.4s
n = 200, 1.6s
n = 300, 3.6s
n = 500, 10s
n = 700, 19s
n = 1000, 40s
n = 2000, 2.7min
n = 5000, 17min
…
n = 10000, +1h