title: How to define which field a treestore should display as node text with ExtJS 4
body: <p>In my ExtJS 4 app, I have a Model (with one field "name"), a Treestore and a Treepanel. I want the Treepanel to display the "name" field of my model. How can it be specified ? 
  Default Nodes have a "text" field, which is displayed on the tree. But isn't it possible to tell the Tree to display someting else from the Model ?</p>
  
  <p>thank you</p>