title: matplotlib.legend.set_zorder() doesn't work in ipython notebook
body: <p>here's a quick thing which is quite annoying me. I've followed the indications found in  <a href="https://stackoverflow.com/questions/16770049/strange-matplotlib-zorder-behavior-with-legend-and-errorbar">strange matplotlib zorder behavior with legend and errorbar</a> but it doesn't work. Here's a very brief working example</p>
  
  <pre><code>x = np.linspace(0,10) 
  y = (x-5)**2 
  plt.plot(x,y,label='test curve',zorder=100)
  plt.legend(loc='center right').set_zorder(102)
  </code></pre>
  
  <p>If you try this you will see that the legend is still underneath the curve, despite the <code>zorder</code>ing. Does anyone know why?</p>
  
  <p><img src="https://i.stack.imgur.com/MOekP.png" alt="http://i.stack.imgur.com/MOekP.png"></p>
  
  <p>I'm using matplotlib 1.3.1 on ipython 3.1.0</p>