title: Extjs date column format
body: <p>i have date column with datefield editor. The problem is that while im editing column it displays the normal value for example <code>2013-02-05</code>, but when close editing it displays something like <code>Sat Jul 12 2014 00:00:00 GMT+0300 (FLE Standard Time)</code></p>
  
  <p>My code: </p>
  
  <pre><code>{
      xtype : 'datecolumn',
      dataIndex : 'depreciationStartPeriod',
      header : 'Depreciation start period',
      sortable : true,
      id : 'depreciationStartPeriod',
      width : 134,
      editor : {
          xtype : 'datefield',
          format: 'Y-m-d H:i:s'
      }
  }
  </code></pre>
  
  <p>store field:</p>
  
  <pre><code>{
      name : 'depreciationStartPeriod',
      type : 'String',
      dateFormat: 'c'
  }
  </code></pre>
  
  <p>what the reasons could be?</p>
  
  <p><strong>UPDATE</strong></p>
  
  <p>in store it is also saved with wrong format for some reason, that's why it is being displayed in such format, but i don`t now the reason of that.</p>