Removed fixed heights for section elements.

Made .vignette position relative when input:checked - this allows parent
element to scale to height of the slider's content
Prototype for CSS only buttonbar - markup and styles
Updated buttonbar prototype to include hover and current page styles
Removed dividers, fixed styling, responsive
Removed btn-border from styles, fixed up head info in html
Added buttonbar to mark-up and adjusted styling
Fixed positioning issues
Fixed positioning issues with middlebit text