squash! first review

ja-JP: first review (debian-doc@debian.or.jp:08255)

* add language code ahead of the commit message (heading "ja-JP: ").
* add origin of the discussion in subject line of the commit message.
* add Checked-By and Ref tags to changed entries according to this proposal.
* add Last-Translator header.
* change fuzzy mark to Vote-Fuzzy tag.

* Proposal-Mail: debian-doc@debian.or.jp:08255
* Proposal-Web: http://lists.debian.or.jp/debian-doc/201607/msg00000.html