createlinks: removed runlevel-adjust and firewall-adjust calls. Refs #1870
*.spec: removed %post / %preun / %postun scriptlet. Refs #1872
nethserver-mail-filter-{conf,uninstall} actions. Removed manage_add and manage_remove calls. Refs #1874
/etc/amavisd.conf template: changed default values logic for SpamCheckStatus and VirusCheckStatus props. Refs #1872
/etc/postfix/master.cf template: enable amavisd on queued messages. Refs  #1870
/etc/postfix/master.cf template:  Override the default content inspection type. Refs #1870
nethserver-mail-filter-conf action: no longer required. Refs #1874