title: Import data - with firebase keys
body: <p>I am trying to import some data into firebase</p>
  
  <pre><code>{
  "people": 
    [
      {
         "name": "John Smith",
          "age": 23,
      },
      {
          "name": "Tony Jones",
          "age": 61,
      },
  ]
  }
  
  </code></pre>
  
  <p>This is fine but it adds a "traditional" array index in firebase (0,1) - which I believe is bad?</p>
  
  <p>When I insert a new value via my web form I get a mix </p>
  
  <pre><code>
   "0" : {
       "name": "John Smith",
        "age": 23,
    },
   "1" : {
       "name": "Tony Jones",
        "age": 61,
    },
    "-LgWkhX2DdD_ChbWJkXo" : { // inserted via form it has a firebase index
       "name": "Simon Green", 
        "age": 37,
    }
  
  </code></pre>
  
  <p>How can I get the initial inserted data to use firebase indexes it is just a normal .json file. </p>
  
  <pre><code>{
      "people": 
      [
          {
            "name": "John Smith",
           "age": 23,
          },
    {
          "name": "Tony Jones",
          "age": 61,
      },
  
     ]
  }
  </code></pre>