added edd icons font
added icon font styles
added "add to cart" button for ajax use only

- the button contains a spinner icon
changed ajax added message
only print ajax add to cart button if ajax is enabled
ajax add to cart button scripts and styles
wrapped credit card info legend in a span to allow for better styling
checkout form style tweaks

- mostly spacing changes
#edd_final_total_wrap was in a field set, nested in a field set and it contained no fields…so i stopped that
wrapping all checkout fieldset legends in spans
checkout styling tweaks