title: Create a bin for anything above X value in GGPlot2 Histogram
body: <p>Using <code>ggplot2</code>, I want to create a histogram where anything above X is grouped into the final bin.  For example, if most of my distribution was between 100 and 200, and I wanted to bin by 10, I would want anything above 200 to be binned in "200+".  </p>
  
  <pre><code># create some fake data    
  id &lt;- sample(1:100000, 10000, rep=T)
  visits &lt;- sample(1:1200,10000, rep=T)
  
  #merge to create a dataframe
  df &lt;- data.frame(cbind(id,visits))
  
  #plot the data
  hist &lt;- ggplot(df, aes(x=visits)) + geom_histogram(binwidth=50)
  </code></pre>
  
  <p>How can I limit the X axis, while still representing the data I want limit?</p>