Add Japanese translated README

[eltociear]

What does this PR do?

Add Japanese README

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[HuggingFaceDocBuilderDev]

The documentation is not available anymore as the PR was closed or merged.

[sgugger]

Thanks for adding this new translation! @younesbelkada do you want to give it a quick proofreading?
Also @eltociear to make sure the Japanese README stays up to date with the other ones, could you fill the fololowing dict with the proper prompts/templates? Thanks!

[eltociear]

@sgugger Thanks!
Added a fix to the this file.

[younesbelkada]

初めまして @eltociear 👋 !
Thanks a lot for this great PR!
The Japanese translation looks perfect to me, I am really looking forward to merging this!
I would advocate to add something similar to the Chinese translated README, at the beginning of this README file, let's add a dictionary for future contributors and for mapping the important keywords:

<!---
A useful guide for English-Chinese translation of Hugging Face documentation
- Add space around English words and numbers when they appear between Chinese characters. E.g., 共 100 多种语言; 使用 transformers 库。
- Use square quotes, e.g.,「引用」

Dictionary

Hugging Face: 抱抱脸
token: 词符（并用括号标注原英文）
tokenize: 词符化（并用括号标注原英文）
tokenizer: 词符化器（并用括号标注原英文）
transformer: transformer（不翻译）
�pipeline: 流水线
API: API (不翻译）
inference: 推理
Trainer: 训练器。当作为类名出现时不翻译。
pretrained/pretrain: 预训练
finetune: 微调
community: 社区
example: 当特指仓库中 example 目录时翻译为「用例」
Python data structures (e.g., list, set, dict): 翻译为列表，集合，词典，并用括号标注原英文
NLP/Natural Language Processing: 以 NLP 出现时不翻译，以 Natural Language Processing 出现时翻译为自然语言处理
checkpoint: 检查点
-->

Gently tagging our japanese student ambassadors @haruki-N @blackdoor571 @hiro819 if they want to have a quick look ;)

[sgugger]

Thanks! Can you also just quickly run make fix-copies to make the CI happy?

[eltociear]

@younesbelkada さん初めまして！
Thank you for contacting!
I have added an explanation to the top of the README.
Also, thanks for checking and suggesting a fix!

[sgugger]

@eltociear It looks like the start prompt you added is not present in the Japanese README. Could you make sure it's correct?

[eltociear]

@sgugger Thank you for pointing this out. start prompt is here.

[sgugger]

Thanks again for your contribution!

[eltociear]

@sgugger THANKS too!