Improve some comments, and remove a superfluous free.
Improve some comments, and remove a superfluous free.

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