twisted.mail.imap4 docs state incorrect meaning of UNSEEN value

New submission from bobf <None>:

The docs for `IMAP4Client.select()` (http://twistedmatrix.com/documents/current/api/twisted.mail.imap4.IMAP4Client.html#select) state: "UNSEEN: An integer indicating the number of messages not flagged \Seen in this mailbox."

However, the RFC (http://www.faqs.org/rfcs/rfc3501.html) states:

"OK [UNSEEN <n>]
                     The message sequence number of the first unseen
                     message in the mailbox.  If this is missing, the
                     client can not make any assumptions about the first
                     unseen message in the mailbox, and needs to issue a
                     SEARCH command if it wants to find it."

The behaviour of IMAP4Client matches the RFC, not the Twisted docs (i.e. if I have one unread message, UNSEEN is the sequence number of that unread message, not "1").

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Type     : defect
Component: mail
Keywords : 
Priority : normal
Nosy     : 
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http://twistedmatrix.com/trac/ticket/4271