Detect OpenCL 1.0 / 1.1 and use old calls to OpenGL buffer creation.
Fixed incorrect merge.
clCreateFromGLTexture3D must use GL_TEXTURE_3D for all 3D OpenGL buffer types.
Added OpenCL 1.2, 2.0 detection and exception for unknown versions.
Modified DFT tests to allow a maximum of 3% error between the CPU and OpenCL values.
DFT kernel now does shared loads of pixel values. Works on ATI with a slight performance loss on cards with cache.
Added documentation to kernels.
Added test for DFT failures when the DFT size is large and/or not evenly divisible by the local size.
Applied DFT fixes for OpenCL on CPU devices

* Account for local memory allocation in local thread size determination
* Force barrier sync for local memory operations in DFT kernel