Thanks to Info-ZIP for info on the DOS-time/date conversion code,
and some other general information gathered from their sources.

Thanks to these people for suggestions, testing, and bug reports:

Heiko Hund <heiko@ist.eigentlich.net>
Joel Ebrahimi <joel.ebrahimi@gmail.com>
Pierre <pierre.dev@gmail.com>
Roberto Tirabassi <rtirabassi@3di.it>
Stephen Bryant <steve@bawue.de>