Westend Mark II (#983)

* Initial draft

* More work

* Build

* Docs

* Insert westend keys

* Add badBlock to fork from old chain

* Updated spec to reset westend

* Use raw spec

* Fix spec format and use westend2 for both id's

* Correct public key for bootnode 3

* Build

* Extra space

* Fix build

* Lock

* Update lock

* Fixes

* Fix for he startup text

* Bump

Co-authored-by: Gav Wood <gavin@parity.io>