Add Japanese translation for README

[delphinus]

Description

This adds Japanese version of README.

Requirements / Checklist

• Read the Contributing Guidelines
• Read or at least glanced at the FAQ
• Read or at least glanced at the Wiki
• Scripts execute without error (if necessary):
  • If any of the scripts were modified they have been tested and execute without error, e.g.:
    • ./font-patcher Inconsolata.otf --fontawesome --octicons --pomicons
    • ./gotta-patch-em-all-font-patcher\!.sh Hermit
• Extended the README and documentation if necessary, e.g. You added a new font please update the table

[delphinus]

Completed. Review this, please.

[ryanoasis]

Very nice, thank you for the continued contributions! 🏅

It looks good to me (visual scan and spot checked some text)

Edit: I updated #118 with your contribution - checked it off the list