Update mail/postfix pacakge to 2.8.2.

Update mail/postfix pacakge to 2.8.2.

Postfix stable release 2.8.2 is available. This release has minor
fixes that are already in the experimental (2.9) release.

- Bugfix: postscreen DNSBL scoring error.  When a client disconnected
  and then reconnected before all DNSBL results for the earlier
  session arrived, DNSBL results for the earlier session would be
  added to the score for the later session. This is very unlikely
  to have affected any legitimate mail.

- Workaround: the SMTP client did not support mail to [ipv6:ipv6addr].

- Portability: FreeBSD closefrom() was back-ported to FreeBSD 7,
  breaking FreeBSD 7.x support retroactively.

- Portability: the SUN compiler had trouble with a pointer expression
  of the form ``("text1" "text2") + constant'' so we don't try to
  be so clever.