Reworking the model import pipeline

Just a quick update. 

I've been working on getting new set of models into the game. Doing that I ran into a very common problem - models tend to have arbitrary hierarchies and transforms. 

For context, Ex Nihilo is built on a custom engine that I've been working on over the past 6 years or so.

So when you try to untangle that to just "Here's the Geometry. Here's the Material, Here are the animations" - it just doesn't work. It would be possible to make it work, but you would have to write a lot of extra code to achieve that.

So I finally gave up, I decided to support these arbitrary hierarchies inside the game. This adds a bit of overhead in terms of performance, but the asset pipeline gets so much easier that it's worth it.