title: Extjs file upload progress
body: <p>I have seen form file upload example in ExtJS4 and i need customize progress of the file upload.</p>
  
  <p>I see waitMsg config property, but i don't want use that and i don't want use extjs 3rd party plugins.</p>
  
  <p>So, how i can get simply current upload progress from upload form in extjs?</p>