DateTime & TimeSpan handling incorrect

[marcobudde]

My interface uses System.DateTime and System.TimeSpan. Both types are handled incorrectly in the Swagger description:

System.DateTime is exported as type = "string" and format = "date-time". But the format used by WCF is not compliant to RFC3339. So I think "format" should be removed.

System.TimeSpan is exported as complex type "#/definitions/System.TimeSpan". WCF used a format like this "P1D". So I think this type should also be exported simply an "type = string".