Trilaterates the position of a person based on a given 3 beacons and distance to those beacons.
Finds the closest beacon to the person. The point is given a score based on distance to the 3 closest beacons to the person. In order to minimize the effect of an individual beacon's inaccuracy: The point is recursively adjusted until it has the lowest possible score, even if that means venturing outside the range of the first beacon's distance-to-target.