Add start and stop beep support

Requested by the angry mob outside

etc/inc/system.inc

@@ -728,6 +728,7 @@ function system_reboot_sync() {
 }
 
 function system_reboot_cleanup() {
+	mwexec("/usr/local/bin/beep.sh stop");
 	captiveportal_radius_stop_all();
 }
 

etc/rc

@@ -209,6 +209,8 @@ rm -rf /usr/local/pkg/pf/CVS
 
 /usr/local/sbin/check_reload_status >/dev/null &
 
+/usr/local/bin/beep.sh start
+
 echo "Bootup complete"
 
 exit 0