Add date format option for widget

[dominikbell]

The date format in the widget is fixed to the format "Month Day", e.g. "Nov 20". It would be nice to also choose different formats like can be done for the list-items when opening the app and when editing a list item (panel). Seeing the day of the week on one glance without tapping on the list or opening a calendar would be very useful. These are the only two adjustments one can make in the settings.

Proposed solution
Add a third date format option under Settings -> Appearance that lets one adjust the date format in the widgets