Bug 1076706 - [Smart Screen][Home] Implement card listing and launching function

Please review only the commit of Bug 1076706, because the base (bug 1076702) has not landed yet

https://bugzilla.mozilla.org/show_bug.cgi?id=1076706
Yes, its a mockup of deck until we have a real one. Because we haven't discuss how to define a `Deck`. But on my second thought, maybe I could just use `Deck` instead since we are going to modify `Deck` anyway once we have `Deck` definition.