[#11550] make focus prominent
[#11550] add text for slideshow controls
[#11550] screen-readable title for slideshow
Merge branch 'master' into 11550-slideshow-controls

Conflicts:
	themes/agov_base/css/global.css
Merge branch 'master' into 11550-slideshow-controls

Conflicts:
	themes/agov_base/sass/global.scss
Merge pull request #38 from previousnext/11550-slideshow-controls

11550 slideshow controls