Push a new scene example

[vincentfretin]

Push the scene example (.blend file and glb) kindly done by @uhunkler that use most of the hubs components.

[vincentfretin]

Live at https://c-frame.github.io/aframe-gltf-model-plus/examples/playground/index.html
@uhunkler If forgot to add proper credits for your scene. Do you want to add your name somewhere? Feel free to edit the index.html and create a PR.