Enhancement: boxplot2

Hi Olga, I recently attended a conference where a number of immunologists showed a variant of a boxplot like this one
http://www.nature.com/nm/journal/v12/n12/images/nm1511-F1.jpg
So I proceed to hack the matplotlib's default boxplot to resemble this pretty creature. An example rendering is attached below and a working example is a part of the commit. 
![plot](https://cloud.githubusercontent.com/assets/395931/3530509/41643f6a-07a5-11e4-9027-87a9ba74f261.png)
Would you like to incorporate that into prettyplotlib or are you happy with the boxplot from matplotlib?
I realize that the code is probably somewhat incomplete/hacky so I'll gladly make changes.