Show the newsletter when navigating after success (bug 1113354)

![newsletter-refresh-loop mov](https://cloud.githubusercontent.com/assets/211578/5498434/c05a4922-86e4-11e4-91a8-123cf40be74c.gif)

Yeah, I thought of that when I wrote this. I was thinking we should get `main.js` to call this after it renders the footer. Maybe we can have the `newsletter_signup` view pull the config from this module? I'll try and refactor this.