Add Chinese translation for index docs

[waynerv]

We (a small team) are working to complete the doc translation of Chinese version in the next two months.

[codecov]

Codecov Report

Merging #1191 into master will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##            master     #1191   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files          224       226    +2     
  Lines         6728      6785   +57     
=========================================
+ Hits          6728      6785   +57     

Impacted Files	Coverage Δ
fastapi/routing.py	100.00% <0.00%> (ø)
fastapi/encoders.py	100.00% <0.00%> (ø)
fastapi/applications.py	100.00% <0.00%> (ø)
tests/test_skip_defaults.py	100.00% <0.00%> (ø)
tests/test_jsonable_encoder.py	100.00% <0.00%> (ø)
..._tutorial/test_sql_databases/test_sql_databases.py	100.00% <0.00%> (ø)
...est_sql_databases/test_sql_databases_middleware.py	100.00% <0.00%> (ø)
...test_application_configuration/test_tutorial001.py
tests/test_tutorial/test_settings/test_app02.py	100.00% <0.00%> (ø)
...orial/test_sql_databases/test_testing_databases.py	100.00% <0.00%> (ø)
... and 1 more

---

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[RunningIkkyu]

@waynerv I'm working on the Chinese trans too, may I have your wechat or email?

[RunningIkkyu]

Great translations! @waynerv

[waynerv]

@RunningIkkyu Great! You can send your wechat to my gmail: ampedee@gmail.com. I will contact you later.

[llxlr]

天哪，有翻译的人了，我也自己开了个翻译项目，我感觉自己在做无用功

[Dustyposa]

天哪，有翻译的人了，我也自己开了个翻译项目，我感觉自己在做无用功

has interested in join our team? my email zmzposa@outlook.com

[tiangolo]

This is amazing! Thanks everyone for doing this! 🚀 🌏 💬

And special thanks for the reviews from others, that's key here, as I don't know Chinese 😅

When others feel like this is complete, that there are no more corrections necessary, and hopefully that the style of "conversation" is similar, please add a new review approving the changes of this PR.

That way, after seeing that there's some consensus on the translation I'll be able to merge it. 🎉

[tiangolo]

@Dustyposa do you think this is ready? You can let me know with a review approving it 😄 👍

@phy25 if you have the chance, could you help me with a review here?

I'm just waiting for more reviews approving it before merging. 🌐 🚀

[waynerv]

@tiangolo I can ask the Chinese community for some help. More and more Chinese developers have started to use FastAPI recently.

[lpdswing]

checked, i approve this

[tiangolo]

This is awesome! 🚀 🌏 🙇

Thanks for all the work @waynerv ! 🍰 👏 🎉

Thanks for the reviews and comments @RunningIkkyu , @Dustyposa , @lpdswing , @jamesyangget 💪 🤓 🙇 🍰