Twenty Fourteen: optimize featured content lookup to reduce the number of queries for featured posts. Props Chouby and obenland, closes #26744.
Built from https://develop.svn.wordpress.org/trunk@29174


git-svn-id: http://core.svn.wordpress.org/trunk@28958 1a063a9b-81f0-0310-95a4-ce76da25c4cd