[L10N] Kickoff for Git 2.12.0 l10n round 2

Hi guys,

Git v2.12.0-rc1 introduced another two new messages need to be translated, so let's start l10n for Git 2.12.0 round 2:

    l10n: git.pot: v2.12.0 round 2 (2 new)

    Generate po/git.pot from v2.12.0-rc1 for git v2.12.0 l10n round 2.

    Signed-off-by: Jiang Xin <worldhello.net@gmail.com>

You can get it 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