todo

* Object that represents the opengl state machine. Directly address slots etc
* Copy between buffer (gpu-arrays)
* Research safe foreign data initialisation so an error does cause a memrory leak 
  look at with-foreign-object for hints
* read http://www.opengl.org/wiki/Buffer_Object and look at the buffer corruption section
* base-macros....what is in here and why

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* make-gpu-array with list is failing 
  ok at really odd  times so is from gl-array... this is odd
  seems to be when created using defparameter...so it doesnt like
  top level for some reason?

* We need a representation of frame buffers...or whatever those 
   things are! I kind of feel that running a shader should return
   one. At the very least we will need it later for targets and
   for defining feedback within pipelines.

* add set culling? combined enabling, setting winding-order and
  cull-face in one move.

* stream could have base offset so draw-element-base thingy works

* enable is odd.... can things be made better by spinning out 
  it's functionality to other functions?

* uniform buffer objects

* deletion of things in pools in cepl-gl

* :triangle, :lines, etc are called the render-mode or primitive
   do our arg names reflect this?

* bindbufferrange - read about it

* work through the glossaries of arc-synth and check args names
   in cepl-gl for conformance