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

* git://github.com/git-l10n/git-po:
  l10n: de.po: translate 4 new messages
  l10n: vi.po: translate 4 new messages
  l10n: zh_CN.po: translate 4 new messages
  l10n: Update git.pot (4 new, 3 removed messages)

Author: gitster