Get the jurisdiction code of a license.
This is usually a two-letter ISO 3166-1 alpha-2 code, but there is also the special case of Scotland, for which no code exists and which is thus represented as "scotland".
Known jurisdictions: ar, at, au, be, bg, br, ca, ch, cl, cn, co, de, dk, es, fi, fr, hr, hu, il, in, it, jp, kr, mk, mt, mx, my, nl, pe, pl, pt, scotland, se, si, tw, uk, us, za.
a license reference string in form of a URI, e.g. "http://creativecommons.org/licenses/by-nc-nd/2.0/"
the jurisdiction code of the license, or NULL if the license is unknown or is not specific to a particular jurisdiction.