[L10N] Kickoff of translation for Git 2.6.0 round 2

Hi,

Git v2.6.0-rc2 had been released, and introduced three i18n improvements. Please update your translations based on this commit:

    l10n: git.pot: v2.6.0 round 2 (3 improvements)

    Introduce three i18n improvements from the following commits:

    * tag, update-ref: improve description of option "create-reflog"
    * pull: don't mark values for option "rebase" for translation
    * show-ref: place angle brackets around variables in usage string

    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