☔ Documentation Translation

[MaySoMusician]

Is your feature request related to a problem? Please describe.

The documents in this repository are generally expected to be written in English for better international communications. Actually, however, this might lead the Japanese speakers to have slight difficulties participating the project.

本レポジトリ内のドキュメントは、国際的なコミュニケーションをより良く行うため英語で記述されるのが原則である。しかし実際のところ、それにより日本語話者が本プロジェクトに参加する際に若干の難しさを感じてしまう可能性が考えられる。

Describe the solution you'd like

Some of the documents that will be read so often by the Japanese-speakers should be also available in Japanese.

ドキュメントのうち日本語話者が頻繁に読むであろうものに日本語訳をつける。

Additional context

n/a for now 今のところ特に無し

[MaySoMusician]

I will first translate README.md

[MaySoMusician]

I thought the issue be left opened, at least for a while, in order to track continuously the documents to be translated. @halsk, what's your thoughts?