Treemap issues

[trickvi]

Moved from openspending/openspending#643

/cc @vitorbaptista
Couldn't find the files to make a pull request, so I'm opening an issue here instead.

There's a missing font on the embeddable iframe:
treemap.css#16: font-family: 'OpenSansRegular';

This could be easily fixed by adding the font to the iframe.

As a good practice I would also recommend adding a generic sans-serif font to the stack, making it less shallow and avoiding a 'Times New Roman' as default, which would make the code look something like this: font-family: 'OpenSansRegular', sans-serif;

Also I think it would be awesome if I could add an array of custom colors to the Treemap, since the current ones are destroying my layout. 😢
The call for the color array is at main.js#163.

Checkout original issue for comment