Possible errors

What my tree doesn't have is the nearest neighbor iterator feature, where much of the cost of searching is deferred to the iteration over the results so if you don't need all the points it doesn't need to do a full search. This could be added, but would be fairly tricky.

If there are any other things you think my tree really needs, let me know and I'll see what I can do. Only thing I'm not interested in at the moment are balancing, and reclaiming memory from removing points.