Power

The power analysis notebook. Expanded notebook text is on [google docs](https://docs.google.com/document/d/1CQPlAue1mVFOd811cKGuy4fibFs5abR-wTjaeW6Wu0I/edit?usp=sharing).
Repeatedly add on the same ending item? All of the Greengenes taxonomy strings are 7 level, when will this while loop be used?