Completed Challenge

Deployed to [Heroku](http://arcane-everglades-6572.herokuapp.com/).

I found a world map annotated with ISO-3166 country codes at [Natural Earth](http://www.naturalearthdata.com/downloads/50m-cultural-vectors/) and then converted it to a d3-friendly format like so:

    topojson --simplify 0.00001 --id-property iso_a2,c,254 -o world.topo.json ne_50m_admin_0_countries.shp

This is my first time using Heroku and Flask so it's all a little bare bones.