Site specific consumers answer whether they can handle a URL and when asked
handle the URL, returning another URL from which the data can be downloaded.
This interface doesn't specify exactly what the data is, but specific
implementations will usually only apply to a single data modality.
Typical uses are for the downloading of images on a URL to an image hosting
Sina Samangooei (firstname.lastname@example.org), Jonathon Hare (email@example.com)