populate front properties
move JSON serialisation implicits to companion objects
Merge remote-tracking branch 'origin/master' into facia-metas

Conflicts:
	common/app/model/facia.scala
og:image from facia properties
remove redundant implicit
code format
Merge remote-tracking branch 'origin/master' into facia-metas
remove explicit defaults
remove explicit defaults
Merge pull request #5933 from guardian/facia-metas

Customisable socia media card image