Parse fails with multiple buckets

[riteable]

The parsing breaks when the response is as follows:

var esResponse = {
      "aggregations": {
        "offerId": {
          "doc_count_error_upper_bound": 0,
          "sum_other_doc_count": 0,
          "buckets": [{
            "key": "F1A2LqSYD3u",
            "doc_count": 9,
            "os": {
              "doc_count_error_upper_bound": 0,
              "sum_other_doc_count": 0,
              "buckets": [{
                "key": "Desktop",
                "doc_count": 6,
                "campaignClick": {"value": 6.0},
                "offerClick": {"value": 6.0},
                "revenue": {"value": 0.0}
              }, {
                "key": "Mobile",
                "doc_count": 3,
                "campaignClick": {"value": 4.0},
                "offerClick": {"value": 4.0},
                "revenue": {"value": 0.0}
              }]
            }
          }]
        }
      }
    };

Notice the multiple buckets in the "os" aggregation.

[isabek]

Hey @riteable. You can make a PR. Actually, I don't have time to support this module.