fix isDirty determination for date field
Move list update to onResume()

Updating list in onResume() rather than onActivityCreated()
ensures that is it updated with latest changes (i.e. timezone)
when the users comes back to the app.
use zoneoffset when reading from database

Add date adjustments using zoneoffset when reading from database.
Add zoneoffset to test data.
Update date related comments.
remove incorrect documentation