Updated mailgrey graylisting policy scripts

for my dual (My)SQL-Server Postfix graylisting policy service mentioned in
this blog entry about the two-node redundant SQL postfix graylisting service
are available:

• mailgrey-policy.pl
• mailgrey-periodic.pl

You will need an MySQL Database Version 5 or greater (for InnoDB performance), perl with DBD::mySQL and Digest::MD5, and Postfix capable of using Policy servers.

With this update, changes to the whitelist databases (postmap) are detected automatically. The literal script in the former blog article was updated also.