TimestampField

Sometimes it's very convenient to have an auto populated timestamp field. For example, Riak is not aware of the data types, but you can use range queries while querying the data to get the list of objects for a certain period of time. Besides that, JSON Schema has format definition for timestamps, please see http://tools.ietf.org/html/draft-zyp-json-schema-03#section-5.23 for details.