v1.8.2

• guard against missing gallery element (when the gallery has been changed or closed) (#124)
• fix trapping of the focus inside the overlay in Firefox < 9 (7a39ba5)
• fix hiding the overlay on background click and not working keyboard shortcuts in IE8 (f1b5484)
• multiple documentation updates (8f1d040, 1d368f6, 27d3959 a24dd4d, 8613150)