HTML-shiv for IE8

Internet Explorer 8 does not recognise HTML5 elements and does not render the boxes we have made correctly. To overcome this we have to use a patch called HTML-shiv and some conditional HTML so that only IE8 sees this code.

As time goes by, fewer visitors will be using IE8, so this will become less important, but as long as Windows XP is still alive and kicking, so is IE8.