Log Message:
Use qmail-qfilter's installer, which wins us a manual page. Add
dependency on netqmail (but not qmail, as for pkgsrc purposes this
requires the QMAILQUEUE patch). Enable pkgviews installation. Rename
post-patch to do-configure, since that's what it's doing.

Add a simple script that runs all the filters in ${PKG_SYSCONFDIR}
whose filenames match "qfilter-*". Explain how to enable filtering
on messages arriving via SMTP using this script.

Take MAINTAINER. Bump PKGREVISION.