updates the bolt version to 6639cef095a2ecc7b8f0c48c6e7f2f906fbfbc58.
this requires us to use the new bolt parser at generate-bolt.py
and updates to all of the type specifications (ie. from u8 -> byte)
They were not universally used, and most are trivial accessors anyway.
The exception is getting the channel reserve: we have to multiply by 1000
as well as flip direction, so keep that one.
The BOLT quotes move to `struct channel_config`.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
