Expander text look well centered in iOS. Also, now using a real minus sign.
Merge branch 'master' of github.com:guardian/frontend into expander-vertical-centering

Conflicts:
	common/app/assets/stylesheets/state/_state.scss
Merge branch 'master' of github.com:guardian/frontend into expander-vertical-centering

Conflicts:
	common/app/assets/stylesheets/module/_cta.scss
	common/app/assets/stylesheets/state/_state.scss
Merge pull request #1047 from guardian/expander-vertical-centering

Expander text look well centered in iOS. Also, now using a real minus sign