|Argument dt||The DateTime object to copy into this object|
|Argument t||The type of datetime that should be stored in this DateTime object|
|Description||Populates this DateTime from the data held in dt, converting this DateTime to be of Type t.|
NOTE: DateTime uses the XML Schema formula for proleptic Gregorian calendar where year 0 is illegal and -4 (4BC) as a leap year.
Throws: if the DateTime object does not contain adequate incormation (because of its type) to populate this object with the data requred to be of type t.