First rev -- spinning square, pushing model->world matrices down with the vertices, and pushing a uniform world->view and view->projection matrix with each draw call.  Also mapping alpha values from a texture.  To do: use the (present but not called) tree building code, copied from frontier's desktop version, and display a tree instead.
Finish the tree-building code (from frontier), and draw a "tree".  (Really just the trunk.)  Kill the color attributes.  Realize that positive-Z in the code I'm pulling from is treated as "away from the ground", while positive-Z in webgl is "into the screen".  Likely have to change a bunch of model->world matrices to fix that up, but this works for now.  It just looks weird animating.

Also add a .gitignore to ignore editor swap files.