trash-list
 - it checks that the $topdir/.Trash is a sticky dir
    - it reports when $topdir/.Trash is not sticky
 - it checks that the $topdir/.Trash is not a symbolic link
    - and it warns the user otherwise
 - it lists contents from both Home TrashDir and Volume TrashDirs (both 
   methods)
 - it warns when an empty .trashinfo is found
 - it warns when an unreadable .trashinfo is found
 - is tolerant with .trashinfo that does not contains a DeletionDate
 - is tolerant with .trashinfo that contains an invalid DeletionDate
 - it warns when a .trashinfo does not contains the Path entry
 - print version information on --version
trash-empty:
 - when run with `days` argument it should skip .trashinfo with invalid date
 - print help on --help
 - print version on --version
