title: How to Write to stderr or files in Threepenny
body: <p>I am using Threepenny (hello Heinrich!) to construct an image database GUI.</p>
  
  <p>As part of the diagnostic and development phase, whenever I attempt to write diagnostic files to /static (or anywhere else), Threepenny seems to throw a wobbly (only showing "an exception escaped to toplevel: ServerAppDone". When trying to write to stderr/stdout via print or putStrLn etc, nothing seems to come out onto the Threepenny command window launch screen's text.</p>
  
  <p>Am I missing something here, or does the way Threepenny operate prevent haskell output?</p>