only Material Icon is not converted to outline
Hi, I added 3 icons from FontAwesome, and 1 icon from Material, but when I use the plugin, only the FontAwesome icons are converted.

![screen shot 2016-06-11 at 4 39 26 pm](https://cloud.githubusercontent.com/assets/2784323/15987603/1bc10996-2ff3-11e6-9ada-a9c51318edea.png)

Using 3.8.3 on Yosemite
