test: zone id must be normalized and GregorianCalendar testing

[KyleAure]

Fixes #250
Fixes #230
Fixes #177

• Modify testZoneIdMapping for a ZoneId that does not need to be normalized
• Add testZoneIdMappingNormalized to verify normalization of ZoneId during serialization
• Add testZoneOffsetMappingNormalized to verify normalization of ZoneOffset during serialization
• update testGregorianCalendarWithTimeMapping so that it verifiers the instance of time represented by serialized and deserialized GregorianCalendar equal each other without relying on Calendar.equals()