Milter-greylist

According to Emmanuel Dreyfus:
> 
> If the answer to this question is the second alternative, then I'll 
> immediatly make two releases available:
> 1) 3.0a6, which will be 3.0a4 plus Attila's fixes (MX sync and Tru64 build)
> 2) 3.1.1, which will be 3.0a5 plus your new patches.

I vote for that choice, similar to so many projects.

[ just to let you know...
I'm still running the last 2.1 because I've started a patch implementing
autoblack but it quickly turned into a beast when I changed the db format,
then added per tuple stats (number of hits), then I found out that my
blacklist idea could be turned into a botnet-autoblacklist, which seems
an even better idea but still needs some refinements.
I'm still too far from public release and september being back, I have zero
free time to spend on that.
I pass for now, I'll eventually merge into 3.1, or forget the whole thing
if it gets nowhere. ]

/Fabien