title: Ext.form.ComboBox: Use template for displayField
body: <p>Is there any way to apply a template to the selected value of a ComboBox? I'm using a template to display the drop down values of the ComboBox, but as soon as i select one, the plain value from the datastore is shown.</p>
  
  <pre><code>{
    id:               'requestStatusCombo',
    hiddenName:       'requestStatus',
    tpl:             '&lt;tpl for="."&gt;&lt;div class="x-combo-list-item"&gt;{statusCode:requestStatus}&lt;/div&gt;&lt;/tpl&gt;',
    fieldLabel:       'Status',
    xtype:             'combo',
    mode:           'local',
    triggerAction:     'all',
    store:             new Ext.data.ArrayStore({
        fields:       ['statusCode'],
        data:       [['unassigned'],['assigned'],['closed']]
    }),
    valueField:       'statusCode',
    displayField: 'statusCode'
  }
  </code></pre>
  
  <p>I want to use my format function <code>requestStatus</code> to translate the <code>statusCodes</code> into locale spesific status names, and this works well for the drop down list, but as soon as I select something, the <code>statusCode</code> is shown.</p>
  
  <p>So is it possible to assign a template to the displayField, or perhaps do some simple batch modification on the datastore? By processing the input through a reader maybe? Is there another <code>&lt;tpl for="?"&gt;</code> keyword that will make this happen? </p>
  
  <p>I'm looking for some simple method utilizing the Ext library. If the only solution is to pre process the data, I'm capable of doing that myself.</p>