Period Constructor
There are five overloads for the constructor.
Overload List
| Period | Default constructor |
| Period(Period) | Copy constructor |
| Period(String) | Construct a period from a string in ISO 8601 period format |
| Period(DateTime, Duration) | Construct a period from a start date and a duration |
| Period(DateTime, DateTime) | Construct a period from a start date and an end date |