G-API: Kernel package design (#13851)
* Remove cv::unite_policy from API
* Add check that all id in kernel package are unique
* Refactor checker id procedure
* Remove cv::gapi::GLookupOrder from API
* Implement cv::gapi::use_only
* Fix samples
* Fix docs
* Fix comments to review
* Remove unite_policy
* Fix GKernelPackage::backends()
* Fix comments to review
* Fix all_unique
* Fix comments to review
* Fix comments to review
* Remove out of date tests
Extend optical flow tutorial (#14314)
* extend python optical flow tutorial with cpp example code and add it to general tutorial directory
* remove unused parameters, fix comparison between signed and unsigned int
* fix hsv range problem
* switch to samples::findFile for sample file location
* switch to command line parameter for path
* remove old tutorial as in 14393
* minor fixes
Extend meanshift tutorial (#14393)
* copy original tutorial and python code
* add cpp code, fix python code
* add camshift cpp code, fix bug in meanshift code
* add description to ToC page
* fix shadowing previous local declaration
* fix grammar: with -> within
* docs: remove content of old py_meanshift tutorial, add link
* docs: replace meanshift tutorial subpage in Python tutorials
* switch to ref to fix wrong breadcrumb navigation
* switch to cmdline for path as in #14314
* Apply suggestions from code review
* order programming languages alphabetically
Grammatical errors for help() in detect_mser.cpp (#14122)
* Grammatical errors for help() statement
Corrected spelling of "synthetic" and added grammatical clarification for keys to press to change view or use mouse.
* Adjustment of superfluous spaces
* Created python version of the code for the anisotropic image segmentation tutorial. Created python/cpp toggles for the markdown file.
* fix doxygen warnings
Many of the Android samples rely on an options menu to work properly
but, at least on newer devices, the menu is permanently hidden by the
Android theme "Theme.NoTitleBar.Fullscreen", which means that most
of the examples were dysfunctional.
