[G-API]: Adding reshape for CNN input.

* Added CNN input IE reshape

* rbs

* Added unordered_set instead vector

* Alignment

[G-API] Introduce cv.gin/cv.descr_of for python

* Implement cv.gin/cv.descr_of

* Fix macos build

* Fix gcomputation tests

* Add test

* Add using to a void exceeded length for windows build

* Add using to a void exceeded length for windows build

* Fix comments to review

* Fix comments to review

* Update from latest master

* Avoid graph compilation to obtain in/out info

* Fix indentation

* Fix comments to review

* Avoid using default in switches

* Post output meta for giebackend

[G-API] Support multiple asynchronous requests

* Support nireq option

* Disable tests to check CI

* Fix bug with hanging

* WA to green CI

* Snapshot

* Simplify RequestPool

* Add default values to id

* Fix win warning

[G-API] Async infer request hotfix

* Fix hanging on empty roi list

* Prevent possible data race

* Clean up

[G-API] Implement async infer

* Implement async infer

* Fix typo

G-API: ONNX. Const input

* Added const input for ONNX backend

* Returned initMatrixRandu, added some comments, rebase

[G-API] Support GFrame for infer

* GInfer(GFrame), currently broken

* Fixed (API only)

* Support GFrame in GIEBackend

* Fix comments to review

* Fix comments to review

* Fix doxygen

* Fix building with different IE versions

* Fix warning on MacOS
Co-authored-by: NDmitry Matveev <dmitry.matveev@intel.com>
Co-authored-by: NSmirnov Alexey <alexey.smirnov@intel.com>

Expand ie::Params to support config

* Add config to IE params

* Add test

* Remove comments from tests

* Rename to pluginConfig

* Add one more overloads for pluginConfig

* Add more tests

- desync() is a new (and for now, the only one) intrinsic
  which splits the graph execution into asynchronous parts
  when running in Streaming mode;
- desync() makes no effect when compiling in Traditional mode;
- Added tests on desync() working in various scenarios;
- Extended GStreamingExecutor to support desync(); also extended
  GStreamingCompiled() with a new version of pull() returning a
  vector of optional values;
- Fixed various issues with storing the type information & proper
  construction callbacks for GArray<> and GOpaque;

- Introduced a new infer(Roi,GMat) overload with a sample;

- Introduced an internal API for Islands to control fusion
  procedure (to fuse or not to fuse);
- Introduced handleStopStream() callback for island executables;
- Added GCompileArgs to metadata of the graph (required for other
  features).

[G-API] Support ImportNetwork for cv::gapi::infer

* wip

* Refactoring

* Fix comments to review

* Fix warning
Co-authored-by: NRuslan Garnov <ruslan.garnov@intel.com>

[G-API] Introduce generic version for cv::gapi::infer

* Introduce generic infer

* Move Generic to infer.hpp

* Removew num_outs

* Fix windows warnings

* Fix comments to review

* Fix doxygen

* Add comment

* Fix comments to review

* standoalone ifdef in ginfer.cpp

* Fix test

[GAPI] RMat integration into the framework

* RMat integration

* Added initialization of input mat in GArray initialization tests

* Fixed klocwork warnings in RMat tests, changed argument order in EXPECT_EQ

[G-API]: Add GOpaque and GArray serialization support

* Add GOpaque and GArray serialization support

* Address review comments

* Remove holds() method

* Address review comments

* Remove comments

* Align streaming with kind changes

* Fix kind in kernel

* Address review comments

GAPI: Migration to IE Core API

* Migration to IE Core API
 - both versions are maintained
 - checked building with all the OpenVINO versions (2019.R1, R2, R3, 2020.4 (newest))

* commit to awake builders

* Addressing comments
 - migrated to Core API in 'gapi_ie_infer_test.cpp'
 - made Core a singleton object
 - dropped redundant steps

* Addressing comments
 - modified Mutex locking

* Update

* Addressing comments
 - remove getInitMutex()
 - reduce amount of #ifdef by abstracting into functions

* return to single IE::Core

* Divide functions readNet and loadNet to avoid warnings on GCC

* Fix deprecated code warnings

* Fix deprecated code warnings on CMake level

* Functions wrapped
 - All the functions depended on IE version wrapped into a cv::gapi::ie::wrap namesapace
 - All this contained to a new "giebackend/gieapi.hpp" header
 - The header shared with G-API infer tests to avoid code duplications

* Addressing comments
 - Renamed `gieapi.hpp` -> `giewrapper.hpp`, `cv::gapi::ie::wrap` -> `cv::gimpl::ie::wrap`
 - Created new `giewrapper.cpp` source file to avoid potential "multiple definition" problems
 - removed unnecessary step SetLayout() in tests

* Enabling two NN infer teest

* Two-NN infer test change for CI
 - deleted additional network
 - inference of two identical NN used instead

* Fix CI fileNotFound

* Disable MYRIAD test not to fail Custom CI runs

* G-API: Introduce a new gapi::infer2 overload + gaze estimation sample

* G-API/infer2: Introduced static type checking for infer2

- Also added extra tests on the type check routine

* G-API/infer2: Addressed self-review comments in the sample app

- Also fix build on Linux;

* G-API/infer2: Remove incorrect SetLayout(HWC) + dead code

- Also fixed comments in the backend

* G-API/infer2: Continue with self-review

- Fix warnings/compile errors in gaze estimation
- Dropped the use of RTTI (VectorRef::holds()) from the giebackend
- Replaced it with a trait-based enums for GArray<T> and std::vector<T>
- The enums and traits are temporary and need to be unified with
  the S11N when it comes

* G-API/infer2: Final self-review items

- Refactored ROIList test to cover 70% for infer<> and infer2<>;
- Fixed the model data discovery routine to be compatible with new
  OpenVINO;
- Hopefully fixed the final issues (warnings) with the sample.

* G-API/infer2: address review problems

- Fixed typo in comments;
- Fixed public (Doxygen) comment on GArray<GMat> input case for infer2;
- Made model lookup more flexible to allow new & old OMZ dir layouts.

* G-API/infer2: Change the model paths again

* G-API/infer2: Change the lookup path for test data

* G-API/infer2: use randu instead of imread. CI war is over

G-API: Mat's "deownification"

* deowned Mat

* boner

* Removed canDescribe test for own::Mat

* Removed STANDALONE flag for apply() and operator()

* Removed: desc_tests for own::Mat, descr_of for own::Mat.

* Returned: tests, cv::gapi::own::descr_of; fixed alignment; Removed own::Mat's headers

* Removed unused header own/mat.hpp from gbackend.hpp

G-API: GOpaque implementation

* Stub initial copypasted solution

* Fix mov test and add a couple of others

* Fix warnings

* More code coverage and tests

* fix macos warning

* address review comments

* Address review comments and fix indentation

* Fix build on armv7

G-API: Introduced Security Barrier & Interactive Face Detection samples

* G-API-NG/Samples: Added samples & relevant changes

- Security barrier camera sample
- Age/Gender/Emotions recognition sample
- GIEBackend now loads CPU extension libraries
- A couple of API-level workarounds added to deal with cv::Mat/Blob conversions

* G-API-NG/Samples: removed HAVE_INF_ENGINE remnants

Introducing the sample of Face Beautification algorithm implemented via Graph-API

* Introducing the sample of Face Beautification algorithm implemented via Graph-API
- 'gapi/samples/face_beautification.cpp' added
- FIXME added in 'gcpukernel.hpp'

* INF_ENGINE fix
- preprocessing clauses added not to run the sample without Inference Engine

* INF_ENGINE fix 2
- warnings removed

* Fixes
- checking IE version cut as there is no dependency
- some alignments fixed
- the comment about preprocessing commands fixed

* ie::backend() issue fix (according to dmatveev)
- as the sample needs the cv::gapi::ie::backend() to be defined regardless of having IE or not, there is its throw-error definition in `giebackend.cpp` now (by dmatveev)
- for the same reason, #includes in `giebackend.hpp` are fixed
- HAVE_INF_ENGINE check is removed from the sample

* - headers in "infer/" and "infer/ie/" folders are included into gapi_ext_hdrs;
+ because of that a few #includes are required in the headers
- HAVE_INF_ENGINE flag check in headers "infer/ie.hpp" and "infer/ie/util.hpp" is deleted

* - the "ie/util.hpp" header is a private header now as it's used for tests; it's been moved to the scr directory to the place next to the implementation file "ie/giebackend.cpp"
- the path to this header in files "ie/giebackend.cpp" and "test/infer/gapi_infer_ie_test.cpp" is updated
- As it's private header now and explicitly depends on IE, the "HAVE_INF_ENGINE" flag check is returned

Found using `codespell -q 3 -S ./3rdparty -L activ,amin,ang,atleast,childs,dof,endwhile,halfs,hist,iff,nd,od,uint`

* 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