datatypes in jsonld are not defined in @context

[DavidLeoni]

Inside values there is indicated the datatype, i.e. "dataType": "NLSTRING". but "NLSTRING" is not defined in @context. it would be better to put a jsonld @type tag like "@type":"NLSTRING"

"attributes": [{
            "creationDate": 1411057967173,
            "modificationDate": 1411057967173,
            "conceptId": 2,
            "dataType": "NLSTRING",
            "values": [{
                    "creationDate": 1411057967174,
                    "modificationDate": 1411057967174,
                    "dataType": "NLSTRING",
                    "operator": "EQUAL",
                    "value": "Andalo",
                    "languageCode": "en"
            }]

See http://www.w3.org/TR/json-ld/#typed-values