Add support for Draco/Meshopt compression

Some notes:
- WebAssembly is directly supported on some JavaScript VMs like V8.
- There are some issues on the JS side that prevent things like Draco to work.

As of this writing, the following error is stopping Draco from working in Babylon Native:
> Unable to load from https://raw.githubusercontent.com/KhronosGroup/glTF-Sample-Models/master/2.0/Buggy/glTF-Draco/Buggy.gltf: document.createElement is not a function RuntimeError: Unable to load from https://raw.githubusercontent.com/KhronosGroup/glTF-Sample-Models/master/2.0/Buggy/glTF-Draco/Buggy.gltf: document.createElement is not a function