Provide alternative methods to Sakai Time object

Currently the sui generis Sakai Time interface is deprecated as java.util.Date should rather be used. However many sakai objects offer no alternatives as they return Time objects.

The api's shoudl offer an alternative method that returns a Date with the origional time one marked as deprecated. On can convert from a Time to date as:

Time m_lastModifiedTime ...
new Date(m_lastModifiedTime.getTime()

and

Time mytime = timeService().newTime(new Date().getTime());