Use Json for each Virtual Object

[ignacio-chiazzo]

Handle each object by Json. Also, we should allow adding models automatically by just adding the asset to Models.scnassets.

Resources: Apple Project Documentation

cc: @NordyVlasman @ericviston

[NordyVlasman]

Just an idea, loading online models or something. Like you download a zip file from the internet and it shows it in AR. ARKit accepts dae files..