Add pretty print methods to KDTreeNode and KDTreeNodeGPU.
Merge branch 'master' of https://github.com/jeremynewlin/Accel
Add debug method to verify correspondence between CPU and GPU kd-tree structures.
Add stackless intersection method that can run on device.
Fix bug in stackless GPU traversal algorithm.
Add CUDA kernel to perform obj ray casting via stackless kd-tree traversal.