Bug 6739: (follow-up) handle case where patron has no expiration date set

Signed-off-by: Galen Charlton <gmc@esilibrary.com>
Bug 11262: (follow-up) base generation of day name on a week starting with Sunday, not Monday

This fixes test failures reported by
t/db_dependent/Serials/GetNextSeq.t.

Signed-off-by: Galen Charlton <gmc@esilibrary.com>