Milter-greylist

Hi,

Attached is a patch which supercedes my previous patches for the Received-SPF header and nodkim.

On the nodkim feature: I dropped it as I generally don't find it useful. I was really after suppressing the DKIM log messages which the attached patch still achieves. 

On the Received-SPF aspect:  I've extended the string formats to also include SPF and DKIM results, and Authentication-Results.

Currently running this patch (with my postfix queue ID patch) with libopendkim and libspf2; all seems to be working well so far.
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Steven Hiscocks