Add volume control for sounds

From @gitpet (#143):

Thanks for the ticker sound! I love using it. I just wish it was possible to reduce the timer tick sound volume independently from the other sound notifications, since it's too loud and can become stressful.

From Babak on CWS:

Ability to configure the volume and duration of alerts

From benlind on GitHub:

I would like a way to adjust the volume of all the sound effects (especially the "when complete" sounds).

From Ricardo on CWS:

It only lacks a sound volume bar.

From Jason on CWS:

My only gripe is that I can't reduce the volume of the timer ticking sound. I really want the ticking on, but it's too loud. However I don't want to just turn my system sound down, because then the alarms will be too quiet.

• Volume control for timer tick and alert sounds
• Store in sync settings

@schmich I support your idea for volume control.

It appears that it was added and then removed. Can you explain what was the challenges that lead to the removal?

@GrooveCS It was never added. I was originally against it since I didn't want to bloat the extension with yet more settings, but it's apparent that it's needed now. I'm planning to add it for sure, it's just a matter of priority.

+1