Notify User if the talk page exists

Upon typing a title, the plugin will check for the main page, the talk
page, a draft page in the format 'draft:title' and the talk page for the
draft, in that order of importance

Known issues: The error message flashes a little when the name is being
typed, due to the different namespaces being checked.

http://www.google-melange.com/gci/task/view/google/gci2014/5877487489777664
https://github.com/WPAFC/afch-rewrite/issues/26
Why are you using `fail` here? `api.get` only fails if unable to connect to the API... in which case rawData wouldn't returned at all.

You can just use 

```js
AFCH.api.get( {
   ...
} ).done( function ( rawData ) {
```

:)