Performance tuning.
Started working on a ray tracer. Found a fixed a few missing match clauses, but there are still more to come.
Merge branch 'master' into raytrace
More work on the raytracer. It compiles now, but we're getting the weird error about unitialized kernel arguments again.
Rendered a circle (there's no shading yet). Unfortunately, we have trouble passing ADTs to kernels as free variables.
Add some shading to the raytracer (#80)