* Using sphinx-multiversion to support multiple version
of python api document
* change python api sidebar link
* fix whitelist_externals deprecated and add git
close: #8227
* [python] Add task decorator for python function
* Add decorator `@task`
* Add a tutorial about it
* Change tutorial doc and combine into traditional docs
* Add sphinx-inline-tab for better view
* revert not need change
* Correct python function indent
* Correct integration test
* Add basic cli mechanism with Click, for now just including
one single subcommand `version`
* Add general and easy test class in tests/testing/cli, and
test to version
* Add sphinx-click to general cli docs basic on click
Jiajie Zhong