* Remove chains.

* Move relay clients.

* Flatten generic.

* Fix fmt.

* use runtime:: prefix for message-lane pallet traces

* renamed message-lane (module and primitives) folder into messages

* replace "message lane" with "messages" where appropriate

* make finality verifier pallet instantiable

* add second instance of finality verifier pallet to the Millau runtime

* add Westend -> Millau headers relay

* use wss to connect to public westend nodes

* initialize with best_finalized_block

* typo

* Revert "initialize with best_finalized_block"

This reverts commit 954ed283.

* pass VoterSet by ref

* new bridge initialization code

* loop upper bound

* Polkadot -> Westend

* fixed tests compilation

* default-features

* assert

* Move chain primitives to a sub-folder.

* Update workspace members.

* Extract core parts of polkadot.

* cargo fmt --all

* Remove TODO.

* cargo fmt --all

* Fix crate names.

* Add to the latest API.

* cargo fmt --all

* Add nested lock files to ignore (generated during cargo fmt)

* Fix compilation.

* cargo fmt --all

* Fix ignore pattern.

* Address review comments.