title: How to change collapsible position in panel extjs4?
body: <p>When I give <code>collapsible : true</code> in panel, collapsible icon (up arrow) is showing at the right most side. How I can show it on left side of the panel?</p>
  
  <pre><code>Ext.create('Ext.panel.Panel', {
      title: 'New Section',
      height: 275,
      width: 530,
      margin: 3,
      collapsible : true
  });     
  </code></pre>
  
  <p>after that I am dynamically editing title using <code>setTitle(text)</code> method. The title will be changed but the collapsible will not show up. Can any one know what is happening here?</p>
  
  <p>Thanks in advance</p>