TODO

* Implemenet @gpu to handle size transformations. Perhaps some kind of
  overridable partial application is needed. (done!)

* Implement wrapping for allt types at the level of
  pygpu.compiler.interpreter so that the type of an object can be
  accessed via the type-member.  (need to extend type-space with
  Python types such as sequences and functions, better to keep the
  python types except when emitting PyGPU functions?) 

* Implement recursive compilation (partially done, not properly tested!)

* Implement differently sized framebuffers with caching (see ATI-compatability)

* Complete Cg backend (partially done!)

* Implement both 1D and 2D image processing modes

* Implement tests/examples using dynamic branches (simple done!)

* Implement ATI-compatability

* Correct line-number reporting and better error messages

* Implement 16-bit mode (maybe?)