title: Firebase data sorting by date stamp
body: <p>Ia am working on an app that receives <code>datamessages</code> with <code>timestamp</code> in the format <code>"yyyy/MM/dd kk:mm:ss"</code>. here is the JSON data  format.</p>
  
  <pre><code>"NOT20170828132901" : 
  {
            "code" : "Your order status has been updated to Rejected",
            "date" : "2017/08/28 13:29:01",
            "title" : "Order update  SPB20170825095233542"
  }
  </code></pre>
  
  <p>i want to sort the <em>NOTNUMBER</em> based on the latest timestamp. I tried with <code>limitToLast(i)</code> and also <code>limitToFirst(i)</code> but in vein. The result is  <strong>Ascending order</strong>. Iwant the datestamp to be sorted in <strong>Descending order</strong>. I also tried using <code>startAt(futuredatestamp).endAt(pastdatestamp)</code> but not working. I want to sort in this ay:</p>
  
  <pre><code>"NOT20170828140827" : {
            "code" : "Your order status has been updated to Rejected",
            "date" : "2017/08/28 14:08:27",
            "title" : "Order update  SPB20170825095233542"
          },
          "NOT20170828140436" : {
            "code" : "Your order status has been updated to Delivered",
            "date" : "2017/08/28 14:04:36",
            "title" : "Order update  SPB20170825095233542"
          },
          "NOT20170828132901" : {
            "code" : "Your order status has been updated to Rejected",
            "date" : "2017/08/28 13:29:01",
            "title" : "Order update  SPB20170825095233542"
          },
          "NOT20170828115852" : {
            "code" : "Your order status has been updated to Rejected",
            "date" : "2017/08/28 11:58:52",
            "title" : "Order update  SPB20170825095233542"
          },
          "NOT20170828014147" : {
            "code" : "Your order status has been updated to IN TRANSIT",
            "date" : "2017-08-28 01:41:47",
            "title" : "Order update : SPB20170825095233542"
          }
  </code></pre>
  
  <p>Little confused in using filter parameters.</p>
  
  <p>Please help me. Thank in advance</p>