Retrieves a list of entity names which can have data retrieved using QueryAdditionalData. 

Use the GetAdditionalDataFieldsForEntity function to get the definitions of fields within an entity. 

A token is passed for authentication. If the authentication fails, or other errors occur, no data will be returned. The result of the authentication is represented by a TAuthenticate object. 

This function has security level "Unrestricted", and can be accessed by any authenticated user.

[WebMethod(Description = "Gets a list of all entities currently supported by the additional data functions")]
public TAuthEntityList GetAdditionalDataEntityNames(string token);