Linux::usermod - modify user and group accounts

 This module adds, removes and modify user and group accounts
 according to the passwd and shadow files syntax (like struct
 passwd from pwd.h). It is not necessary those accounts to be
 system as long as $Linux::usermod::file_passwd,
 $Linux::usermod::file_shadow, $Linux::usermod::file_group,
 $Linux::usermod::file_gshadow are not in "/etc" directory.