CMake fixes#1367

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pavanky merged 3 commits intoarrayfire:hotfix-3.3.2from

shehzan10:cmake-fixes

Mar 29, 2016

Commits on Mar 24, 2016

More detailed message about CUDA computes in CMake
shehzan10
committed
Disable JPEG_GREYSCALE flag in imageio if not defined in freeimage header file
shehzan10
committed

Commits on Mar 28, 2016

If CUDA_CUDA_LIBRARY is not found, check for stub and throw error
shehzan10
committed