This algorithm moves along the circle and removes the overlapping of the nodes laid out on a circle maintaining a custom gap between them. O(n), doesn't use trigonometry. Relaxation sometimes cannot be completed in one sweep, cause it moves nodes in one direction: clockwise.
Special case is when a node is pushed across the 0° mark.
forked from w8r's block: Removing overlaps on radial layout
https://unpkg.com/d3@4.4.1