function Octree(aabb, options){
    options = options || {};
    options.root = null;
    options.aabb = aabb;
    OctreeNode.call(this, options);

    /**
     * Maximum subdivision depth
     * @property {number} maxDepth
     */
    this.maxDepth = typeof(options.maxDepth) !== 'undefined' ? options.maxDepth : 8;
}
@class Octree
@param {AABB} aabb The total AABB of the tree
@param {object} [options]
@param {number} [options.maxDepth=8]
@extends OctreeNode