l10n: git.pot: proposed updates since v1.8.4 (72+)

The 1st round of Git l10n often starts very late duing the release
cycle of Git, usually after the release of rc0. This leads to a
gaint update of "po/git.pot" and lots of works for translators with
a tight deadline (about one week).

This "pu" branch holds proposed updates of the file "po/git.pot" for
Git next release (1.8.5), and will be updated and rewound without
notification when there are remarkable updates for it.

Translators could work on this "pu" branch before the l10n coordinator
starts the 1st round of l10n for this release cycle of Git, and
rebase their works onto the master branch (with the commit for the
1st round of l10n), then send pull request to the l10n coordinator.

Please note:

 1. You may like to have a local "pu" branch to track and update
    your translations.

        $ git remote add git-po git://github.com/git-l10n/git-po.git
        $ git fetch git-po
        $ git checkout -b pu git-po/pu

 2. Because this branch will be rewound occasionally, translators
    SHOULD NOT merge, but SHOULD rebase to this rewound branch
    instead.  (Note: In the following example, you have only one
    commit to be rebased.)

        $ git fetch git-po
        $ git checkout pu
        $ git rebase -i --onto git-po/pu HEAD~1

    (Rebase may conflict because remote branch "git-po/pu" may
    include your updates in remote master branch.)

 3. Update your "po/XX.po".

        $ msgmerge --add-location --backup=off -U "po/XX.po" \
          po/git.pot

 4. Then start to translate "po/XX.po" and commit.

 5. Do not send pull request to the l10n coordinator for
    translations on this "pu" branch.

 6. When the l10n coordinator starts the 1st round l10n for the
    current Git release cycle, translators should update "master"
    branch, and cherry-pick translations from "pu" to "master" branch.
    (Note: In the following example, you have only one commit to
    cherry-pick.)

        $ git checkout master
        $ git pull --ff-only
        $ git cherry-pick pu

 7. Update your "po/XX.po".

        $ msgmerge --add-location --backup=off -U "po/XX.po" \
          po/git.pot

 8. Then start to translate "po/XX.po", commit (--amend), push and
    send pull-request.

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