* added support for plain user specified global memory buffers (user programs have full and direct access to these and are responsible for any modifications and any synchronization that might be necessary - in the end, these are just kernel parameters that are directly passed through to the user programs main function; syntax is similar to the oclraster_images syntax, but with standard OpenCL C types and with each entry specifying a separate buffer)
 * modified the gfx2d_font shader to make use of oclraster_buffers for the text data instead of a constant memory uniform buffer (fixes amd issues and has the odd side-effect of decreased compilation time)
 * amd/ati gpus are now fully working on os x (ftr: don't use the built-in mix function on any opencl device ...)
 * fixed transform program vertex discard (this is actually callable by the user now)
 * updated README (updated requirements + new paper url; thanks for removing the link, nvidia ...)