Hint at tonal colouring on interactives. Fix comment icons not appearing
SCSS validation
Merge branch 'master' into tonal-interactive-header

Conflicts:
	applications/app/views/fragments/interactiveBody.scala.html
Fix margin on meta container on interactives
Remembering why I added that line of CSS
Merge pull request #6742 from guardian/tonal-interactive-header

Add tonal colour hints interactive header