Allow multiple MeasurementUsage values

Table 6.140: QualityControlResult Resource MeasurementUsage? enumeration enumerations @MeasurementUsage SHALL specify the usage usages of this QualityControlResult. Allowed values are: Master - The measurement values defined in subelements of this QualityControlResult specify a master measurement e.g. a signed press sheet. All subsequent measurements with @MeasurementUsage="Standard" SHALL be compared to the this master measurement. If this QualityControlResult/@MeasurementUsage also contains "Standard", this measurement shall be compared to the previously defined master measurement or absolute setup defined in QualityControlParams. Standard - The measurement values defined in subelements of this QualityControlResult are measurement values that SHALL be evaluated regularly.