Just a small tweak for the campaign's progress bar

Thanks for making this open source! I don't know much nodejs, but it's always interesting to see how these things are put together. Anyway, I hope you don't mind me nitpicking your work :)
Attached is a screenshot of what (I predict) will happen when the campaign inevitably reaches its goal.

![screen shot 2014-02-15 at 5 34 11 pm](https://f.cloud.github.com/assets/401283/2179128/578864d6-9691-11e3-9642-7795df204205.png)

If you had some other solution planned, my Express inexperience prevented me from seeing it so you can just disregard this.