Split codec into @polkadot/types-codec (#4329)
* Split codec into @polkadot/types-codec
* Additional (test cleanups next)
* Fix tests
* Imports from '@polkadot/types-codec
* All remaining codec imports (only exports left)
* Bytes -> types-codec
* Cleanups
* Bool, BitVec, Text movements
* sanitize move
* Adjust (first build fixes)
* Adjust
* Additional
* Adjust
* Adjustments
* linting
* Adjust, not working atm
* Move {U,I}{8,16,32...} to types-codec
* createTypeUnsafe
* Fix type-only exports
* Folder exports
* Split Lookup/Create on registry interfaces
* Clanup LookupRegistry & CreateRegistry
* Combine CreateRegistry into LookupRegistry