Merge pull request #6 from mitsuruog/master

[監訳希望] Variables
着手中/予定コンテンツをアップデート
Japanese translation from Mixins to Rest Parameters
Merge pull request #8 from yukihr/master

Mixins から Rest Parameters までの日本語翻訳
Merge pull request #7 from mitsuruog/master

[監訳希望] Interpolation
Reflect issue #1
Wikify translation contents
add ja translation for import.md for supervise
Update README.md
Update README.md
Merge pull request #9 from yukihr/master

[監訳希望]import.mdの日本語翻訳