[G-API] Extend compileStreaming to support different overloads
* Make different overloads
* Order python compileStreaming overloads
* Fix compileStreaming bug
* Replace
gin -> descr_of
* Set error message
* Fix review comments
* Use macros for pyopencv_to GMetaArgs
* Use GAPI_PROP_RW
* Not split Prims python stuff
G-API: Wrap render functionality to python
* Wrap render Rect prim
* Add all primitives and tests
* Cover mosaic and image
* Handle error in pyopencv_to(Prim)
* Move Mosaic and Rect ctors wrappers to shadow file
* Use GAPI_PROP_RW
* Fix indent
G-API: Support vaargs for cv.compile_args
* Support cv.compile_args to work with variadic number of inputs
* Disable python2.x G-API
* Move compile_args to gapi pkg
G-API: New python operations API
* Reimplement test using decorators
* Custom python operation API
* Remove wip status
* python: support Python code in bindings (through loader only)
* cleanup, skip tests for Python 2.x (not supported)
* python 2.x can't skip unittest modules
* Clean up
* Clean up
* Fix segfault python3.9
Co-authored-by: Alexander Alekhin <alexander.a.alekhin@gmail.com>