Only send tripwire emails if something has changed

src/freedombone

@@ -9869,6 +9869,8 @@ function intrusion_detection {
   chmod +x /usr/bin/reset-tripwire
 
   sed -i 's/SYSLOGREPORTING.*/SYSLOGREPORTING =false/g' /etc/tripwire/twcfg.txt
+  # only send emails if something has changed
+  sed -i 's|MAILNOVIOLATIONS.*|MAILNOVIOLATIONS = false|g' /etc/tripwire/twcfg.txt
   sed -i '/# These files change the behavior of the root account/,/}/ s/.*//g' /etc/tripwire/twpol.txt
   sed -i 's|/etc/rc.boot.*||g' /etc/tripwire/twpol.txt
   # Don't show any changes to /proc