#107 add scaling to the lightbox

this might need some fiddling to ensure correctness
add styling for the press page (`::`)
use $(window).height() instead of $figure.height()
specify the `::` for the press page to apply only to `<dd>`
fix press list styling
finish resizing images to fit the screen
Merge pull request #109 from tim-evans/master

Resize images dynamically according to the viewport and add some basic press styling