The ArchiveEntry function has a number of arguments that can be
considered optional.  Split them out into a separate struct, to make the
API more flexible for changes.

Author: Dmitry Dolgov
Discussion: https://postgr.es/m/CA+q6zcXRxPE+qp6oerQWJ3zS061WPOhdxeMrdc-Yf-2V5vsrEw@mail.gmail.com