Use 4 pixels for one unit. Some ocl code refactoring
Optimize OpenCL LUT function
Optimize OpenCL LUT function
Fix some errors
Fix some errors
Optimize openCL version of reduce function
Change buffer cols count from 64 to 32
fix code in the kernel
Fix some errors
Removed useless multiplication by 4
Merge pull request #2793 from alalek:run_android_env
Moved new kernels under conditional compilation to disable their build for 3-channel images; added condition to use new kernels only for images that are big enough
Updating missed defines in documentation

Updating missed defines in documentation. The new defines (in imgproc.hpp) state they have a prefix of COLOR instead of CV.
opencl opticaflow fix that enables buffer2image extension
2 fixed unassigned reshapes in em (#3674)
Merge pull request #2796 from berak:b_3674_24
Adding explicit variable conversion in ocl_medianFilter() to suppress build errors on Linux & Mac
optimized index access
optimized cv::meanStdDev
optimized index calculation