[Delivers #82528174] Playlab Embeddable iFrame

This feature allows any iFrame to be embedded into e.g. a multiple-choice assessment question.
It also creates a stripped-down embeddable format suitable for embedding Play Lab games into a small frame:
![image](https://cloud.githubusercontent.com/assets/56541/5022316/e121f948-6a97-11e4-854f-969189dd347e.png)


Seconding Dave's comment that this should be fully responsive.

On Thu, Nov 13, 2014 at 10:52 AM, Laurel <notifications@github.com> wrote:

> In dashboard/app/views/layouts/application.html.haml:
>
> > @@ -1,5 +1,6 @@
> >  !!! 5
> > -- show_footer = !(@share && browser.mobile?)
> > +- show_footer = !(@share && browser.mobile?) && !@embed
>
> is it possible to render without a layout instead of parameterizing the
> application layout? Or do you need all of the tags and css and javascript
> to be included again inside the iframe?
>
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