Adds address search functionality to the app

You'll notice there's a couple of methods floating around here...

```javascript
$.when( fetchCoordsForAddress() ).then(
    someCallbackOnPass(),
    someCallbackOnFail()
);
```

and this...

```javascript
var dfd = jQuery.Deferred();

// ...some async stuff...

return dfd.promise();
```
I'm experimenting with this to see if it's a better way to handle asynchronous JSON than calling $.getJSON straight up. Think of it as a getJSON, with custom validation logic, for right now.