copy the traslations of unchanged parts. refs #515
translate updated parts. refs #515
modify comment out style. refs #515
update the translation. refs #515
Merge branch '2.2.x' into issues_515
Merge branch 'issues_515' into 2.2.x
Merge branch '2.2.x' of github.com:playframework-ja/translation-project into 2.2.x