New insight: EOY Most favliked post of the year
closes #2133
[WIP] EOY insight header and landing page
Add ?yearend=1 to the querystring to see the landing page
[WIP] EOY landing page backend

TODO:

InsightDAO tests
InsightEOYStreamController tests
Issue #2128: EOY Biggest Fans insight
Issue #2129: EOY Most talkative day
Issue #2154: EOY All About You insight
Create dedicated EOY test suite
Staging: Test EOY Most Favliked
Staging: Test EOY Most Talkative day
Staging: Test EOY Biggest Fans insight
Staging: Test EOY All About You insight
Tweak EOY landing page design aka Less is more

Mute tomorrow’s teaser
Remove sub-head and share buttons