Added image example to readme
![Lighting example](https://asny.github.io/three-d/0.10/lighting.png)
+## Image [[code](https://github.com/asny/three-d/tree/master/examples/image/main.rs)] [[web](https://asny.github.io/three-d/0.10/image.html)]
+
+![Image example](https://asny.github.io/three-d/0.10/image.png)
+
## Fog [[code](https://github.com/asny/three-d/tree/master/examples/fog/main.rs)] [[web](https://asny.github.io/three-d/0.10/fog.html)]
![Fog example](https://asny.github.io/three-d/0.10/fog.png)
