If you previously configured with `--enable-developer` we turn that into `--enable-debugbuild`.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-Removed: build: `--enable-developer` arg to configure (and DEVELOPER variables): use `./configure --enable-debugbuild` and `developer` setting at runtime.
Update the lightningd <-> channeld interface with lots of new commands to needed to facilitate spicing.
Implement the channeld splicing protocol leveraging the interactivetx protocol.
Implement lightningd’s channel_control to support channeld in its splicing efforts.
Changelog-Added: Added the features to enable splicing & resizing of active channels.
