Optimization of cv::pyrDown for 8UC1.
Use fma only for Intel devices
Change global buffer to local
Change groups count for Intel
DShow camera as IVideoCapture object
Remove unused variable
fix build
enabled BufferPool
Merge pull request #2935 from vbystricky:oclopt_meanStdDev
Merge pull request #2963 from ilya-lavrenov:tapi_bufferpool
Merge pull request #2918 from vbystricky:oclopt_reduce2
Merge pull request #2962 from alalek:fix_v4l_build
Merge pull request #2882 from akarsakov:ocl_pyrDown_opt
Merge pull request #2947 from vbystricky:capDShow
Split highgui module to videoio and highgui
Merge branch 'highgui_split' of https://github.com/vbystricky/OpenCV into highgui_split