Paid invoices need to know how much was actually paid: both for the case
where no 'msatoshi' amount was specified, and for the normal case, where
clients are permitted to overpay in order to help them disguise their
payments.
While we migrate the db, we leave this field as 0 for old paid
invoices. This is unhelpful for accounting, but at least clearly
indicates what happened if we find this in the wild.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
'rhash' is the old terminology, but 'payment_preimage' and
'payment_hash' were decided on for the BOLTs, so we should fix that here.
We still use rhash internally, but that's much easier to fix.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
