title: NUnit Categories in combination?
body: <p>In my NUnit testfixtrues i have something along the lines of</p>
  
  <pre><code>[Test,Category("catA")]
  public void test1
  {
      //
  }
  
  [Test,Category("catB")]
  public void test2
  {
      //
  }
  
  [Test,Category("catA")]
  [Test,Category("catB")]
  public void test3
  {
      //
  }
  </code></pre>
  
  <p>Now in the NUnit gui i want to be able to select catA and catB and run the tests where catA <strong>and</strong> catB are present.  Currently this is not the case and NUnit will run all 3 tests.  </p>
  
  <p>Is there any way to change this behavior to an AND condition rather than OR?</p>
  
  <p>I'm currently running v2.5.0.9122.</p>
  
  <p>Thanks in advance.</p>