general:
- all iterative tests have been replaced with parameterized tests
- old-style try..catch tests have been modified to use EXPECT_/ASSERT_ gtest macros
- added temporary files cleanup
- modified MatComparator error message formatting

imgcodecs:
- test_grfmt.cpp split to test_jpg.cpp, test_png.cpp, test_tiff.cpp, etc.

videoio:
- added public HAVE_VIDEO_INPUT, HAVE_VIDEO_OUTPUT definitions to cvconfig.h
- built-in MotionJPEG codec could not be tested on some platforms (read_write test was disabled if ffmpeg is off, encoding/decoding was handled by ffmpeg otherwise).
- image-related tests moved to imgcodecs (Videoio_Image)
- several property get/set tests have been combined into one
- added MotionJPEG test video to opencv_extra

- cmake dependencies search (WITH_MFX option)
- raw H264, H265, MPEG2 encoding and decoding
- tests for supported formats

compute() for BP and CSBP output 32-bit floating-point mat, and in cv::imshow() 32-bit floating-point is recognized as [0,1] and maped to [0,255], that causes gray window for BP and CSBP.

 - check if compiler is Intel compiler
 - remove not referenced variables

added v_reduce_sum4() universal intrinsic; corrected number of threads in cv::getNumThreads() in the case of GCD

 - fix the define condition based on the comment