Update README.md

[cyamasak]

Additional contributors to create duo_japanese.

[mcourtot]

Hi @cyamasak
2 options:

• you want to highlight them as contributors to the Japanese version: we should then create an entry in the doc for this and add them there
• you prefer to just have everybody part of the general contributors: can you then please put them in alphabetical order with the other contributors?

I'm slightly leaning towards the second one but as you prefer.

Thanks,
Melanie