The command is useful in case the synchronizer reaches an invalid state and you
want to roll back a few blocks and try again (maybe with some fixes in the
code).

- In config, add Debug.MeddlerLogs to enable meddler debug logs.  This only
  affects the node started via cli, tests swill ran with `meddler.Debug = true`
- Remove unused ethereum client functions and config parameters
- Document all the config parameters