Complete the API for soy.bodies.Mesh, soy.atoms.Face, and soy.atoms.Vertex

soy.bodies.Mesh is a list-like sequence of soy.atoms.Face

soy.atoms.Face has (at least)four properties - 3 verticies (a, b, c) and material. Additional properties for smooth, etc, can be added later.

soy.atoms.Vertex is position, normal, texcoord, and tangent for a vertex.

All data (materials, the faces which use them, and verticies) need to be stored in the Mesh as arrays. Verticies and Faces may be added to more than one Mesh.

Rendering is not needed or expected to complete this task, but the Python API should be fully usable.

While working on this task you should join and remain in #PySoy on Freenode to get help, feedback, and guidance from mentors and other developers. Code updates which may affect your work are also announced here as they happen.

When you've done, commit your work and post the resulting changeset url to this task.