Clustermap

add clustered heeatmap and correlation plots

example clustermap

![image](https://cloud.githubusercontent.com/assets/806256/5156827/fa0ef118-72b2-11e4-923b-f79dd2fad046.png)

example correlation plot

![image](https://cloud.githubusercontent.com/assets/806256/5156829/0803d14e-72b3-11e4-9854-102363d86ebc.png)