title: Automatically expand Java directory structures in NERDTree
body: <p>Java by convention is pretty keen on directories. Because of this, all the code in my current Grails project is nested 5 directories deep, e.g....</p>
  
  <pre><code>~controllers
      ~com
          ~companyname
              ~teamname
                  ~productname
                   |-[code actually here]
  </code></pre>
  
  <p>There's a similar folder structure under every core Grails directory (services, taglib, unit-tests), which means an awful lot of hitting o and j repeatedly. </p>
  
  <p>Is there any clever way this can be automated and mapped to a key combination?</p>