New branch for clamsmtpd testing

Added Clamsmtpd for clamav email virus scanning.  Virus email will be dropped and notification will be sent to user in its place.  Tested it on my MIAB as an upgrade, need to test as full install

tools/email_virus_notify.sh

@@ -0,0 +1,45 @@
+#!/bin/bash
+#
+# This script will notify users that email was dropped by clamsmtpd.
+#
+# Original inspiration from this script: https://h4des.org/blog/index.php?/archives/308-clamsmtp-informing-recipients-abount-email-virus-infection.html
+
+source /etc/mailinabox.conf # load global vars
+# For all variables passed when running this script please see "man clamsmtpd.conf"
+
+#pull list of all emails served by this mailserver
+dest_email=$(/usr/bin/sqlite3 /home/user-data/mail/users.sqlite "select distinct source from aliases union all select distinct email from users;")
+
+# check every single recipient
+for i in $RECIPIENTS; do
+
+# check every single email/alias
+for j in $dest_email; do
+
+#check if email address contains hosted domain name
+# $i contains email address
+# $j contains hosted email
+if [[ "$i" == "$j" ]]
+then
+{
+echo "Hello $i,"
+echo ""
+echo "This is the email system of $PRIMARY_HOSTNAME."
+echo "" 
+echo "The email from $SENDER to you was infected with a virus ($VIRUS)." 
+echo "The email was blocked and this notification was sent instead." 
+echo "" 
+echo "If you encounter further problems please contact your System Administrator." 
+echo "" 
+echo "Regards," 
+echo "The email server at $PRIMARY_HOSTNAME"
+#sending email to recipient that is hosted on this system
+} | mail -a "From: postmaster@$PRIMARY_HOSTNAME" -s "Email Virus Scan Notificaton" "$i"
+#continue with next recipient
+
+fi
+
+done 
+
+done
+