MFH: r483810

mail/mailman: add OPTION to not send passwords in the monthly mails

• this option is now on by default

PR: 231879
Reported by: several users
Approved by: mandree
Obtained from: https://mail.python.org/pipermail/mailman-users/2016-April/080746.html
Approved by: ports-secteam (riggs)