Added some trees

[Sjael]

Thought to try my hand at a tree shader, and this project served as some reference for shaders in general, so I decided to drop it in. The vertex shader has a wind effect using simplex noise, and the fragment shader is doing the stylized effect with spherical normals. (I left in one of your old trees as an homage)

I also added some ambient and directional light, also repositioned the camera.

The leaf lighting is not reacting fully to the light direction yet, I'll probably fix that next.

~~I wasn't up to date for your recent commits, sorry about that!~~ fixed it