title: ELK Watcher use array compare for nested buckets
body: <p>I am using ELK watcher for alerts version 2.2, i have my query output something like this </p>
  
  <pre><code>{
      "took": 549,
      "timed_out": false,
      "_shards": {
      "total": 1040,
      "successful": 1040,
      "failed": 0
  },
  "hits": {
  "total": 468101,
  "max_score": 0,
  "hits": [ ]
   },
   "aggregations": {
     "2": {
       "buckets": [
       {
        "6": {
          "doc_count_error_upper_bound": 0,
          "sum_other_doc_count": 0,
            "buckets": [
               {
                 "1": {
                 "value": 84.86304909560724
                 },
               "key": "hostname",
               "doc_count": 10000
        }
  
  
           ]
   },
      "key_as_string": "2016-11-09T19:00:00.000Z",
      "key": 1478718000000,
      "doc_count": 47855
  }
  </code></pre>
  
  <p>in the condition of the watcher i want to compare if "value" is greataer than some threshold, </p>
  
  <p>i tried using array_compare but it does not work for nested arrays like this one
  it matches for fields upto sum_other_doc_count but does not go further.</p>
  
  <p>if anyone can help me with this</p>