(Month view) Improve user interface for days not belonging to current month
In many cases gnome-calendar displays fields for days that don't belong to the current month. These can be improved:
- All days not belonging to the current month should be visibly marked as "disabled", e.g. greyed out.
- When clicking on one of these days gnome-calendar should go to the next/previous month. This is implemented e.g. on Maemo on the Nokia N900 device.