* refined QRCodeDetector API for OpenCV 4.0

* expanded and tested QRCodeDetector::detectAndDecode()

* integrated the new C++ persistence; removed old persistence; most of OpenCV compiles fine! the tests have not been run yet

* fixed multiple bugs in the new C++ persistence

* fixed raw size of the parsed empty sequences

* [temporarily] excluded obsolete applications traincascade and createsamples from build

* fixed several compiler warnings and multiple test failures

* undo changes in cocoa window rendering (that was fixed in another PR)

* fixed more compile warnings and the remaining test failures (hopefully)

* trying to fix the last little warning

* Updated ICV packages and IPP integration

* core(test): minMaxIdx IPP regression test

* core(ipp): workaround minMaxIdx problem

* core(ipp): workaround meanStdDev() CV_32FC3 buffer overrun

* Returned semicolon after CV_INSTRUMENT_REGION_IPP()

  * use boundingRect instead of manual loop

- drop unnecessary matrix initialization

Update hog.cpp (#12649)

* Cleanup macros and enable expansion of `__VA_ARGS__` for Visual Studio

* Macros for enum-arguments backwards compatibility

* Convert struct Param to enum struct

* Enabled ParamType.type for enum types

* Enabled `cv.read` and `cv.write` for enum types

* Rename unnamed enum to AAKAZE.DescriptorType

* Rename unnamed enum to AccessFlag

* Rename unnamed enum to AgastFeatureDetector.DetectorType

* Convert struct DrawMatchesFlags to enum struct

* Rename unnamed enum to FastFeatureDetector.DetectorType

* Rename unnamed enum to Formatter.FormatType

* Rename unnamed enum to HOGDescriptor.HistogramNormType

* Rename unnamed enum to DescriptorMatcher.MatcherType

* Rename unnamed enum to KAZE.DiffusivityType

* Rename unnamed enum to ORB.ScoreType

* Rename unnamed enum to UMatData.MemoryFlag

* Rename unnamed enum to _InputArray.KindFlag

* Rename unnamed enum to _OutputArray.DepthMask

* Convert normType enums to static const NormTypes

* Avoid conflicts with ElemType

* Rename unnamed enum to DescriptorStorageFormat

define itself is still here for compatibility

Minor improvement to SSE code in HOGDescriptor::computeGradient, replace emulation of _mm_mullo_epi32 with constant multiplicand 3 with two _mm_add_epi32. OpenCV issue #11161

Found via `codespell`

Implementation of bit-exact resize. Internal calls to linear resize updated to use bit-exact version. (#9468)

If there are no OpenCL/UMat methods calls from application.

OpenCL subsystem is initialized:
- haveOpenCL() is called from application
- useOpenCL() is called from application
- access to OpenCL allocator: UMat is created (empty UMat is ignored) or UMat <-> Mat conversions are called

Don't call OpenCL functions if OPENCV_OPENCL_RUNTIME=disabled
(independent from OpenCL linkage type)