zanata_stat.py does not work with new Zanata (3.9.6)

[Akihiro Motoki]

Zanata 3.9.6 changes the format of translation stats.

The new format is like:

    {
        "username": "amotoki",
        "contributions": [
            {
                "locale": "ja",
                "translation-stats": {
                    "translated": 7360,
                    "needReview": 0,
                    "approved": 152,
                    "rejected": 0
                },
                "review-stats": {
                    "approved": 220,
                    "rejected": 0
                }
            }
        ]
    }

Previously, the format was:

  {"amotoki":
    [
      {"ja":
          {"translated": 10,
            "approved": 0,
            "rejected": 0
           }
      }
    ]
  }

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/442390
Committed: https://git.openstack.org/cgit/openstack/i18n/commit/?id=07d3753a7f04b9b97abd59d94db4e184adf513bc
Submitter: Jenkins
Branch: master

commit 07d3753a7f04b9b97abd59d94db4e184adf513bc
Author: Akihiro Motoki <email address hidden>
Date: Tue Mar 7 11:11:09 2017 +0000

    zanata_stat.py: Support Zanata 3.9.6

    Zanata 3.9.6 changes the format of statistics data.
    This commit updates the tool to support 3.9.6.

    The old format from the old Zanata used at translate.openstack.org
    is no longer supported.

    Closes-Bug: #1670638
    Change-Id: I692a995142529c4df1e2664264afc19496bf71ed