Map tweaks

Probably most relevant to @msecret and @ericronne 

* Updates all of the country codes to [ISO-3166](http://en.wikipedia.org/wiki/ISO_3166-1). This resolves an issue where no country would be highlighted
* Fixes an issue with SVG transforms resulting in the center of the view not matching the center of the country
* Zoom is now proportional to the country size -- small countries get lots of zoom, big countries get zoomed out. There is an upper bound on the amount we zoom out
* Zoom level is such that there is a "gutter" of 90% the country size visible around the selected country. This gets cut off a bit by the circular mask, so what's truly visible is substantially less
* Border thickness is now a result of the zoom level through some guesstamated break points

![screen shot 2014-11-19 at 2 18 33 pm](https://cloud.githubusercontent.com/assets/326918/5113832/aa0d8e52-6ff8-11e4-9cbd-77058870669d.png)
![screen shot 2014-11-19 at 2 18 59 pm](https://cloud.githubusercontent.com/assets/326918/5113833/aa0e0256-6ff8-11e4-85ae-a71d57fdc3a2.png)
![screen shot 2014-11-19 at 2 20 18 pm](https://cloud.githubusercontent.com/assets/326918/5113834/aa0f2bcc-6ff8-11e4-8389-ed60bc85ae6b.png)