header_parse_semi_param_list

Parses a header which is a semicolon-delimited list of something like: `token [ "=" ( token | quoted-string ) ]`.

Tokens that don't have an associated value will still be added to the resulting hash table, but with a null value.

This also handles RFC5987 encoding (which in HTTP is mostly used for giving UTF8-encoded filenames in the Content-Disposition header).

Parameters:

header

a header value

Returns:

a GenericSet of list elements, which can be freed with [ func@header_free_param_list].