[Docs] Add registry tutorial (#3)

* [Docs] Configure the documentation

* fix the format

* introduce the usage of default_scope

* add Chinese documentation

* move docs configure to another pr

* clean pr

* refactor registry docs

* fix typo

* fix typo

* reorg

* add more examples

* reslove comments

* reslove comments

* reslove comments

Co-authored-by: ZwwWayne <wayne.zw@outlook.com>