Add two bugs related to empty archives, noted by Esben Mose Hansen.
Add two bugs related to empty archives, noted by Esben Mose Hansen.

JanX2/libzip-git,projedi/libzip,cysp/libzip,cysp/libzip,cysp/libzip,projedi/libzip,cysp/libzip,projedi/libzip,JanX2/libzip-git,projedi/libzip