Audible notification

[linuxcdeveloper]

I've got some idea of additional mean of notification. Sometimes it is needed to switch from graphical X11/Wayland environment to virtual terminal and do some work there. If this activity uses networking then usually opensnitch silently blocks application in this activity and the notification is visible only after returning to X11/Wayland.

From end user POV the application just hanged without any error message. In this case it would be fine to have some additional notification from opensnitch-ui just by some "beep" to inform user about some notification event from opensnitch-ui.