Bug 1094094 - [Stingray] Implement Navigation of Apps Deck

1. Enable app launch in app-deck
2. refine styling based on UI/UX spec (though it is not completed yet)
3. l10n work of app-deck
4. refer to the patch of bug 1098274, add 'pin to home' functionality
I'd suggest we make comment on somewhere / or open a follow-bug to confirm these code of getting screenshot wouldn't lost.