…d to create output - primarily for JSON applications

…s and externally provided rates from being used in the system (externally, like modules providing streamlined sales tax lookups, etc). Before tax_rate_data_fetch, the rate_value section of data is unset, so hasRateValue() is ALWAYS null, as there is no reference to the calculation model passed into the event. Without this fix, one has to override this model to fix the event