Adds a dae2sbk converter script.
Adds a skeleton for a Path submodule.
Fixes old StateLogger bug.
Fixes Asset loading callbacks and Traversal bugs.

This patch fixes a bug wherein Traversals didn't create and/or pass on a
State object during construction. Further, it vastly improves the
granularity of Asset loading by using AssetLoading Callback (with
caveats).
Removes silly print() statement in test.
Small culling example changes/cleanup.