Rename DateTime, Date, Time types to DateTimeAsDate, DateAsDate, TimeAsDate and implement DateTime, Date and Time derived from Calendar

[highsource]

[highsource]

See this for the rationale.

Jsonix Schema Compiler now generates DateTime, Date and Time types instead of Calendar. But these types were previously mapping date/time values as the JavaScript Date object which is not compatible with Calendar.

To reduce backwards-incompatibility for schema-derived mappings, DateTime, Date and Time must be compatible to Calendar. To achieve this we'll do the following:

• Rename old types DateTime, Date and Time to DateTimeAsDate, DateAsDate, TimeAsDate accordingly.
• Implement new types DateTime, Date, Time as extensions of Calendar.