restructuring to hold the enum

CI working.

check ci setup

check ci setup

don't refer to master

Initial port

(mirror of https://github.com/paritytech/substrate/commit/b13319a076bbc17ac86e31828143a0c185467263#diff-931ba1dbef01e4bae948c538070714a3e556444658a065b877a813dc309a2bc0 )