title: Print NominalDiffTime as hours, minutes and seconds
body: <p>I'm surprised nobody has asked this before, but... How do I trivially print a <code>NominalDiffTime</code> as hours, minutes and seconds? (And possibly <em>days</em>, if it happens to be that long...)</p>
  
  <p>For reasons unknown, the <code>Show</code> instance prints total seconds, which is obviously useless. (How long is 13,055.22 seconds? Is that a few minutes? A day? Half an hour? I have no idea!)</p>
  
  <p>There's the <code>FormatTime</code> class, but it doesn't apply to <code>NominalDiffTime</code>.</p>
  
  <p>It seems you can use the <code>floor</code> method to get total seconds as an actual <em>number</em>, but then what do you do with it?</p>
  
  <p>As far as I can tell, <code>DiffTime</code> doesn't help either.</p>
  
  <p>There <em>must</em> be a way to print time durations sanely...</p>