Merge branch 'sy/git-gui-i18n-ja'

Update Japanese translation for "git-gui". * sy/git-gui-i18n-ja: git-gui: update Japanese information git-gui: update Japanese translation git-gui: add Japanese language code git-gui: apply po template to Japanese translation git-gui: consistently use the same word for "blame" in Japanese git-gui: consistently use the same word for "remote" in Japanese