title: change the date format in a grid field ExtJS
body: <p>simple question but I can't figure out how to resolve it.</p>
  
  <p>I'm receiving a date with hour from JSON with this format : </p>
  
  <pre><code>"date_deb":"2013\/12\/28 23:00:00"
  </code></pre>
  
  <p>Note that the \ are for escaping the / and are not displayed.
  I would like to display this dates in this format into my grid :</p>
  
  <pre><code>"28/12/2013 23:00:00"
  </code></pre>
  
  <p>I've tried this into my fields definition:</p>
  
  <pre><code>{name:'date_deb', type: 'date', dateFormat: 'd-m-Y H:i:s'}
  </code></pre>
  
  <p>But it's not working, nothing is displayed.
  By checking the ExtJS docs, I've seen this :</p>
  
  <pre><code>dateReadFormat
  </code></pre>
  
  <p>I'm using ExtJS4.2</p>