[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
* Implement G-API python bindings
* Fix hdr_parser
* Drop initlization with brackets using regexp
* Handle bracket initilization another way
* Add test for core operations
* Declaration and definition of View constructor now in different files
* Refactor tests
* Remove combine decorator from tests
* Fix comment to review
* Fix test
* Fix comments to review
* Remove GCompilerArgs implementation from python
Co-authored-by: Pinaev <danil.pinaev@intel.com>