[Note: I already refactored --annotation for container-related
commands; this one is for manifest-related commands]
This one needed reconciling: one man page said "newly added image",
the other said "specified image", I just reduced that to "image".
If that's not cool, any suggestions on how to make it better? Or,
just reject this PR, we can live with this duplication.
Signed-off-by: Ed Santiago <santiago@redhat.com>