Write a new soy.textures.Texture subclass Bumpmap. This class must act as a sequence of Vector atoms instead of Color but still be usable in the same ways a Texture currently can, including as the sides of a Cubemap.

Outside the scope of this task, this new class will serve as the foundation for special methods such as emboss, do heightmap to dot3 conversion, and make it easier to write Mesh+Bumpmap editing utilities.

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.