title: how to read json with schema in spark dataframes/spark sql
body: <p>sql/dataframes, 
  please help me out or provide some good suggestion on how to read this json</p>
  
  <pre><code>{
      "billdate":"2016-08-08',
      "accountid":"xxx"
      "accountdetails":{
          "total":"1.1"
          "category":[
          {
              "desc":"one",
              "currentinfo":{
              "value":"10"
          },
              "subcategory":[
              {
                  "categoryDesc":"sub",
                  "value":"10",
                  "currentinfo":{
                      "value":"10"
                  }
              }]
          }]
      }
  }
  </code></pre>
  
  <p>Thanks,</p>