more internationalization: locale specific calendars

hello all,

currently, Yii’s date/time localization functionalities is just a formatter in a locale-sensitive manner.

it would be nice to add locale specific calendars, any calendar supported by ICU (e.g. gregorian, persian, islamic, …).

as IntlDateFormatter is out there as part of php 5.3+, I thing it’s easy to integrate Yii’s date/time localization with it.