Alarm sounds that "change", not only get louder

From Anonymous on 2015/05/13 22:17:24 +0000

I often don’t wake up with the app’s alarm sounds because when the alarm is a constant noise, I sort of get used to it. So it would be better for me if an alarm sound not only got louder, but also faster, higher or in any other way different.

Copied from original feature request: