[L10N] Start l10n round 3 for one more l10n update from v2.18.0-rc2

Hi,

Git v2.18.0-rc2 introduced a new l10n update, and it's easy to be fixed, even though there are only two days left for the release of Git 2.18.0.

There are too many l10n updates for Git 2.18.0, and some l10n teams may not have enough time to update. Not worry about that, we can send one more pull request to the maint branch after Git 2.18.0 is released.

Find and update your translations from the usual place:

    https://github.com/git-l10n/git-po/

As how to update your XX.po and help to translate Git, please see "Updating a XX.po file" and other sections in “po/README" file.

-- Jiang Xin