I know this is an unforgivably large diff, but the spec has changed so
much that most of this amounts to a rewrite.
Some points:
* We no longer have "offer_id" fields, we generate that locally, as all
offer fields are mirrored into invoice_request and then invoice.
* Because of that mirroring, field names all have explicit offer/invreq/invoice
prefixes.
* The `refund_for` fields have been removed from spec: will re-add locally later.
* quantity_min was removed, max == 0 now mean "must specify a quantity".
* I have put recurrence fields back in locally.
This brings us to 655df03d8729c0918bdacac99eb13fdb0ee93345 ("BOLT 12:
add explicit invoice_node_id.")
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
1e3cb01546