Hg 89 port lightbox

send action to ApplicationRoute
{{action 'openLightBox' 'light-box'}}
or
{{action 'closeLightBox'}}

to open close light box 
this should allow us to use subclasses for special light boxes
ie. 
{{action 'openLightBox' 'media-light-box' 4}}
to open 4th image in media light box
and this is what I am going to work next!
Actually Ember will apply the dasherized version of the property name as the class. So for instance, `classNameBindings: ['isHidden']` will apply the class `is-hidden` to the element. But I'm not sure what `hiddenUI` would generate... it might be `hidden-u-i`, which is not what we want.

See http://emberjs.com/guides/views/customizing-a-views-element/