code: public static Object fromRDF(Object input, RDFParser parser) throws JsonLdError {
          return fromRDF(input, new JsonLdOptions(""), parser);
      }
docs: Converts an RDF dataset to JSON-LD, using a specific instance of
  {@link RDFParser}, and the default {@link JsonLdOptions}.
  
  @param input
  a serialized string of RDF in a format specified by the format
  option or an RDF dataset to convert.
  @param parser
  A specific instance of {@link RDFParser} to use for the
  conversion.
  @return A JSON-LD object.
  @throws JsonLdError
  If there is an error converting the dataset to JSON-LD.