Updated octree to r59 and reworked octree example

This only changes files in the examples folder. Octree changed to handle vertices (and particle systems), removed some slow checks such as isNaN, and added deferred object insertion. Initially when I ported the Octree to r59, I hooked the renderer as a post plugin to insert deferred objects, but after some thought I removed that in place of a manually called update to give user more control. Also added option to skip deferral and return to previous method (which is slightly worse on performance). See also #2148.