end of expression.
(parse_tag, parse_tag_body): Split parse_tag into two functions.
(parse_valid): Placeholder for real function.
(parse_version): New function.
(parse_skip_optional): New function.
(spki_cert_parse_body): New function.
(spki_cert_parse): New function.

Rev: src/spki/certificate.c:1.7
Rev: src/spki/certificate.h:1.7