4 days on 4 days off alarm for shift workers

From MK on 2015/12/20 05:35:56 +0000

I work 4 days on, 4 days off, adding a feature to set this up would be a great help as I hear alarm on the days I don’t work.

Copied from original feature request: http://urbandroid.uservoice.com/forums/264867-sleep-as-android/suggestions/11151450-4-days-on-4-days-off-alarm-for-shift-workers