Milwaukee, WI Added!

Hello Marcin!

Mike Massie and I worked up a changelist that adds Milwaukee, WI to the list of cities!

The following things are still kind of wonky, though:
- there are a ton of neighborhoods in milwaukee and we had to make the size pretty small so we could even see the whole map.
- i built a crappy placeholder graphic for the city name because i didn't know what fonts you used for the city names.

Other than that, i have tested this and it works.  It is also super fun!  I didn't know the names of half of those places in my own town!

-jason gessner

![Screen Shot 2013-02-10 at 11 33 22 AM](https://f.cloud.github.com/assets/396562/143472/02f29976-73a8-11e2-840b-ab9753214659.png)
![Screen Shot 2013-02-10 at 11 33 09 AM](https://f.cloud.github.com/assets/396562/143473/02fb7c1c-73a8-11e2-8864-299ddaddf191.png)
![Screen Shot 2013-02-10 at 11 32 59 AM](https://f.cloud.github.com/assets/396562/143474/02f5b764-73a8-11e2-8f75-8f1583e908bf.png)