Remove facebook most popular a/b test
Add results of Most Popular from Facebook test
Merge remote-tracking branch 'origin/master' into kc-remove-fb-ab

Conflicts:
	core-navigation/app/feed/MostPopularAgent.scala
	core-navigation/app/model/MostPopularLifecycle.scala
Merge pull request #1997 from guardian/kc-remove-fb-ab

Remove facebook most popular a/b test