Emblem.js icon

I don't really know how Icon fonts work, so I left everything as it was and ask you to add the icon to the font.

I've "registered" the icon at `\e61c`. If you want a different code, I'll change it.

The icon assets can be found [here](https://github.com/machty/emblem.js/issues/174#issuecomment-59635569). The icon is subject of discussion (though the project leader already likes it), so you may want to wait a few days.

Thank you for making such an awesome theme!