Fix code formatting.
Put the generateData directly on the scope.
Simplify: just create a treemap object when visualize is called.
Change layout: use the form-horizontal option

This gives a nicer result when there are multiple rows.
Make use of the new d3.treemap.configurations.

Even though there's only one configuration at this point, I added a select
for it already. I also hooked the initial chunk config select to the new
configurations setup. Now I need to fix all possibilities in d3.treemap for
initial chunk configuration to make sure the map renders properly.