Basic date support.
Get date fields.
Freeze the given date.
Set and patch support.

Proxies to setters on date object. Each time creating new version.
Don't freeze user's date objects.
Update method for date.
Don't use Ancient Oak for iteration in test.
Update docs.
Better date desc.
Date does not implement rm method.
Unify notation for methods.
Update date documentation.
Format readme.
Better readability of update method.
More elaborate comment.
Update docs on primitive types.
Merge branch 'dates'