A datatype representing a date or time.
specifications date and times are represented as strings using the ISO 8601 basic
- The date format used is YYYYMMDD.
- Where time is included the format is YYYYMMDDThhmmssZ. The time is separated from
the date by the letter "T" and followed by the letter "Z" indicating that the timezone
July 31st 2012: 20120731 .
13:15 UTC on August 2nd 2012: 20120802T131500Z