After much discussion with Tadge and Laolu, I think we have something
which is nicely outsourcable, and yetnot insanely complex.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Calculations are put in 05-onchain.md, and referred to by 02-peer-protocol.
The number is 600, comfortably under the 626 theoretical limit.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>