Add to Zeppelin Hadoop DFS interpreter

I guees this interpreter can be usefull if you want to do stuff with your HDFS culster.

![screen shot 2014-11-04 at 3 31 12 pm](https://cloud.githubusercontent.com/assets/3139557/4895578/6c45d060-63ec-11e4-81d0-3929e0e5f5d0.png)