title: how to modify store data before loading it into the combo list
body: <p>I have a combo field with <code>queryMode: 'remote'</code> and the store has a structure similar to this:</p>
  
  <pre><code>{
     success: true,
     data: [
       {'name':'john','value':1},
       {'name':'mary','value':2}
     ]
  }
  </code></pre>
  
  <p>How can I remove the first element of the data array if I want to, before it is loaded into the combo list?</p>
  
  <p>I tried capturing the <code>load</code> event and splicing the data array but I didn't seem successful.
  A solution in the context of the one posted in <a href="https://stackoverflow.com/questions/7492689/how-to-get-extjs-4-stores-request-data-on-beforeload-event">this thread</a> would really be helpful.</p>