Fixed: MaxMind provider - fix #183

I requested a demo api key and fixed this provider :)

@boo1ean was right - the api changed I think.

![Screen Shot 2013-01-28 at 3 16 33 PM](https://f.cloud.github.com/assets/672421/103203/623afad4-6955-11e2-84d7-d63d77f5e297.png)