title: How to increase the ipython qtconsole scrollback buffer limit
body: <p>When I load ipython with any one of:</p>
  
  <pre><code>ipython qtconsole
  ipython qtconsole --pylab
  ipython qtconsole --pylab inline
  </code></pre>
  
  <p>The output buffer only holds the last 500 lines. To see this run:</p>
  
  <pre><code>for x in range(0, 501):
     ...:     print x
  </code></pre>
  
  <p>Is there a configuration option for this? 
  I've tried adjusting --cache-size but this does not seem to make a difference.</p>