script to batch process multiple gltfs.

[emileswain]

I'm currently learning how to best prepare gltfs and wanted a way to batch process a bunch of gltfs into a project and would...

1. Copy gltfs into public folder.
2. provide a json file providing settings for each gltf to convert
3. Add shadow cast and receive props to meshes.
4. Resolve a weird behaviour where `export default function Model (){} wouldn't import for some reason. changed to export default (props)=>{}

This is a work in progress, so there is still some tidy up to do, which when i get around to i would ideally address any pull request comments/suggestions.. (i.e. refactor methods from sync to async and wrap up properly into promises.)

[gsimone]

@emileswain there's been a few changes in the lib since the PR was open, let me know if you are still working on this or I'll close in a few days - we can always reopen if you want!

[emileswain]

Sorry, i downed tools completely for xmas. I'll pick this up some time soon hopefully.

[chrisbward]

@emileswain dude! long time!!! I'm giving this a go today - a lot to be desired from docs of this repo... fun fun