title: Show Devexpress WaitForm as dialog
body: <p>I want to show a <code>WaitForm</code> in the user and in the meantime do a long background operation.</p>
  
  <p>I use a <code>Thread</code> for this job and get notified using an event on when the job has been completed.</p>
  
  <p>In this scenario I want to integrate a DevExpress WaitForm.</p>
  
  <p>This form can be shown when the job is going to start (either from inside or outside the thread) and can be stopped upon the completion event fires.</p>
  
  <p>The <code>.ShowWaitForm</code> from <code>SplashScreenManager</code> just shows the form. How can I make the form discard window messages while waiting?</p>
  
  <p>Eg: I don't want the user to be able to click buttons and stuff while waiting.</p>