Is your feature request related to a problem? Please describe.
Currently the Display has a way to emit a "beep". In some case an application might not want this to happen regardless of what library code calls this.

Describe the solution you'd like
We should have a system property (e.g. swt.beep) to control that behavior, it should be assumed to have the value on and off (where no value is interpreted as on) and then completely inhibit beep sounds.

Describe alternatives you've considered
Turn of the speaker or configure the OS to not play sounds but these are rather not acceptable workarounds.

Additional context
This needs to be implemented across all the different OS variants of Display.