#27 Dupecheck and skip idea

[Maksim Ivanov]

I wanna suggest such idea: add to --dupecheck an
option to skip from download and decoding message
that posted in more than x newsgroups. It will be useful
when you download pictures from different groups to
different dirs and now you will get *spam* pics in every
group in message header. Or just another way: if
message crossposted to many group - download and
decode it only in first group.