code: public static double cosineOrHaversineDeg(double lat1, double lon1, double lat2, double lon2) {
      return cosineOrHaversineRad(deg2rad(lat1), deg2rad(lon1), deg2rad(lat2), deg2rad(lon2));
    }
docs: Use cosine or haversine dynamically.
  
  Complexity: 4-5 trigonometric functions, 1 sqrt.
  
  @param lat1 Latitude of first point in degree
  @param lon1 Longitude of first point in degree
  @param lat2 Latitude of second point in degree
  @param lon2 Longitude of second point in degree
  @return Distance on unit sphere