Better error reporting

This is a first pass at this. I decided to work against the CoffeeScript port I have going, for now.

I targeted the browser (over the command line) for formatting of the message. Here's how it looks in the JavaScript console in Chrome:

![screen shot 2014-05-28 at 13 34 04](https://cloud.githubusercontent.com/assets/84700/3108485/cb5cead6-e690-11e3-9d56-bc40386806ff.png)

This implementation still uses `console.error`. Throwing errors doesn't allow such nice formatting from what I can tell, but that doesn't mean we shouldn't do that also. Relates to the-gss/engine#75.

I'm starting to think that this should be a separate module so that other components can reuse it.