in Scripted Trade, add the fixing date in the cashfow information

[quantthingy]

For scripted trades, it looks like the LOGPAY function does not report the fixing date is the cashflow information
From my testing in in c++, the field cf.fixingDate is empty, cf been a CashFlowResults object

Issue
in LOGPAY(X, d, p, ccy), the date d is not into the past and future cashflow object

Suggestion
cf.fixingDate to d

[pcaspers]

That's a good idea, it seems quite natural to populate the fixing date with the observation date of PAY(). We'll add this. Thanks!