Prime Factors: Review for Release

Hey, guys! This was originally made by @austinheimark, and I think it's ready for release. What do you think?

- https://ddh5.duckduckgo.com/?q=prime+factors+of+56
- https://ddh5.duckduckgo.com/?q=prime+factors+of+2

![screen shot 2014-03-26 at 1 08 45 am](https://f.cloud.github.com/assets/81969/2521348/bac6fedc-b4a4-11e3-9d0c-7ada617d5203.png)