* G-API: rename ArgKind OPAQUE to GOPAQUE

Rename ArgKind value to GOPAQUE to fix conflict in the
user code when wingdi.h is included: it defines OPAQUE
macro that (for some reason) is chosen instead of ArgKind
value

* Add compatibility with existing API

* Renamed GOPAQUE to OPAQUE_VAL

* Determine input shapes

* Add test

* Remove getInputShapes

* Fix model

* Fix constructors

* Add Caffe test

* Fix predict

* WINCE 8.0 requires ARMv7 Thumb2 and thus have NEON instructions

* Only add NEON if on _ARM_

Convert HOG from SSE SIMD to HAL - 35-45% faster on Power (VSX) (#15199)

* Convert SSE SIMD to HAL. 35-45% improvement for Power (VSX)

* Remove CV_NEON code. Use v_floor instead of 3 lines of code.

* Invert comparison logic to simplify code.

* Change initialization from v_load to constructor type.

* Remove unavoidable print of CV error

The return value covers whether the device exists.

This might be better hidden behind a debug flag, but I couldn't work out how to do that nicely.

* Use `CV_LOG_WARNING` macro to log rather than removing it entirely

  * add -Wno-psabi when using GCC 6
  * add -Wundef for CUDA 10
  * add -Wdeprecated-declarations when using GCC 7
  * add -Wstrict-aliasing and -Wtautological-compare for GCC 7
  * replace cudaThreadSynchronize with cudaDeviceSynchronize

Support new IE API (#15184)

* Add support OpenVINO R2 for layers

* Add Core API

* Fix tests

* Fix expectNoFallbacksFromIE for ONNX nets

* Remove deprecated API

* Remove td

* Remove TargetDevice

* Fix Async

* Add test

* Fix detectMyriadX

* Fix test

* Fix warning

* in OpenCV.js added 'rotate' function and test sample

* value test added

* G-API-NG/API: Introduced inference API and IE-based backend

- Very quick-n-dirty implementation
- OpenCV's own DNN module is not used
- No tests so far

* G-API-NG/IE: Refined IE backend, added more tests

* G-API-NG/IE: Fixed various CI warnings & build issues + tests

- Added tests on multi-dimensional own::Mat
- Added tests on GMatDesc with dimensions
- Documentation on infer.hpp
- Fixed more warnings + added a ROI list test
- Fix descr_of clash for vector<Mat> & standalone mode
- Fix build issue with gcc-4.8x
- Addressed review comments

* G-API-NG/IE: Addressed review comments

- Pass `false` to findDataFile()
- Add deprecation warning suppression macros for IE

backport of commit: 59b0314a