We had a hack for 'struct rval' in protobuf_convert.h; make an
explicit header and put it in bitcoin/preimage.h. It's not really
bitcoin-specific, but it's better than having bitcoin/script depend on
an external header.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We need some ordering to deliver them to the JSON "waitinvoice" command;
we use a counter where 0 means "unpaid".
We keep two lists now, one for unpaid and one for paid invoices.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>