Add new gltf samples from main repo

[Reon90]

• Iridescence Suzanne
• Iridescence Metallic Spheres
• Iridescence Dielectric Spheres
• Emissive Strength Test
• Unicode Test

[cx20]

I have added those glTF models to the list. However, I haven't updated its status yet. I think it will take some time to update.

[Reon90]

Thank you, Could you please add the StainedGlassLamp, it contains a lot of gltf features.

[cx20]

Thank you for your advice. I added that model to the list.

[Reon90]

Could you please add Mosquito In Amber, it's a stress volume test.

[cx20]

I also added that model to the list.