Pontoon: Updated Japanese (ja) localization of Pontoon Intro
Pontoon: Updated Japanese (ja) localization of Pontoon Intro

Translation authors:
- Kohei Yoshino <kohei.yoshino@gmail.com>
- marsf <chimantaea_mirabilis@yahoo.co.jp>
- dskmori <ghoti.fish.dsk@gmail.com>

mathjazz/pontoon-intro,mathjazz/pontoon-intro,mathjazz/pontoon-intro,jotes/pontoon-intro,jotes/pontoon-intro,jotes/pontoon-intro