KD Tree Nearest Neighbor and Range Search

KD Tree range and nearest neighbor search.

This implements a KDTree for nearest neighbor and range searching.The KDTree stores a N-dimensional set of points. The tree can be queried for all points within a Euclidian range in order O(sqrt(p)+k) time, where p is the number of points and k is the number of reported points. A nearest neighbor search can be done in order O(log(p) time. The m-files are binary MATLAB functions written in C++. Source code is included as well as binaries for Linux on i386 and x86_64 systems and Windows (i386).