Remove expired ports:
2017-03-27 print/musixtex: Broken for more than 6 months
2017-03-27 www/wml: Broken for more than 6 months
2017-03-27 www/offline-npm: Broken for more than 6 months
2017-03-27 x11-themes/kde-icons-cezanne: Broken for more than 6 months
2017-03-27 x11-themes/kde-icons-sky: Broken for more than 6 months
2017-03-27 deskutils/gnome-shell-extension-backslide: Broken for more than 6 months
2017-03-27 devel/openvex: Broken for more than 6 months
2017-03-27 mail/mixmaster: Broken for more than 6 months
2017-03-27 net-mgmt/nat: Broken for more than 6 months
2017-03-27 net-p2p/gnunet-gtk: Depends on expiring net-p2p/gnunet
2017-03-27 net-p2p/gnunet: Broken for more than 6 months
2017-03-27 print/abc2mtex: Depends on expiring print/musixtex