This allows for image paths absolute from the presentation root
This allows for image paths absolute from the presentation root

If the first character of an image path is `/`, then we now assume that
it's absolute from the presentation root. Otherwise, treat it as
relative and do all the legacy wonkery.

binford2k/showoff,binford2k/showoff,marrero984/showoff,marrero984/showoff,binford2k/showoff,marrero984/showoff,puppetlabs/showoff,puppetlabs/showoff,binford2k/showoff,puppetlabs/showoff,marrero984/showoff,puppetlabs/showoff