Basic HTML User Interface

Addresses #2 - isn't pixel perfect, but looks pretty good!
![screen shot 2014-08-05 at 12 25 05 am](https://cloud.githubusercontent.com/assets/1168853/3808054/9897689e-1c71-11e4-9ebe-2bd3ad44b23c.png)

No grapher field yet, of course. This should be enough to get started hooking in all of the different components.

I'd like to open three followup issues after this is merged:

1. Update styles for radio button and file selects: these are not needed now and should be pushed back until after we have a working app.
2. Add [chosen](http://harvesthq.github.io/chosen/) for select boxes: will be a much better interface, but is a nice to have since people can still manually select from select boxes.
3. Add select box for choosing a file from the calchart server (this will be able to get done after the server has all the correct endpoints).

I added hooks to the parts of the UI that will be intractable: basically, clicking on any intractable component logs a message to the console.

@kmdurand, let me know if this works for you!