added CV_16SC2 && CV_16UC1 map types support to ocl::remap (INTER_LINEAR mode)
added ROI support to ocl::buildWarp*Maps functions
added an accuracy test for ocl::buildWarpPerspectiveMaps
fixed ocl::cvtColor for CV_YUV2BGRA and CV_YUV2RGBA
added YCrCb to RGB, BGR, RGBA, BGRA modes to ocl::cvtColor
color.cpp refactoring: created generic interface for toRGB and fromRGB callers
added RGB -> XYZ conversion to ocl::cvtColor
added XYZ to RGB conversion to ocl::cvtColor
added RGB[A] <-> BGR[A] conversion to ocl::cvtColor
replaced custom PI by OpenCL M_PI constant
Make Integral sum support cv_32f, sqsum support cv_64f.
fix warning.
added RGB5x5 <-> RGB conversion
Merge pull request #1780 from ilya-lavrenov:ocl_m_pi
added a performance test for ocl::buildWarpPerspectiveMaps; moved warps to a separate file
Fixed the "image sequence" capture not failing when a pattern isn't found.

at can't be a null pointer, so the condition was always false, and
a nonsensical pattern like "image.png%00d" was being inferred.
removed 2000x2000, 4000x4000 from test sizes of ocl::adaptiveBilateralFilter
Replaced the image used in the Highgui_Video.ffmpeg_image test.

Our prebuilt FFmpeg Windows binaries don't have PNG support enabled
(because that requires zlib), so that makes a PNG image a bad choice
for this test.

When FFmpeg doesn't support PNG, VideoCapture falls back to the
"image sequence" implementation, which doesn't work for single images.
added RGB5x5 <-> Gray
fix some bug about haar and match_template.