Final changes to config sub-system (#8600)

- Introduces changes such as certain types of
  errors that can be ignored or which need to 
  go into safe mode.
- Update help text as per the review

cmd/config/cache/legacy.go

@@ -34,10 +34,6 @@ func SetCacheConfig(s config.Config, cfg Config) {
 		return
 	}
 	s[config.CacheSubSys][config.Default] = config.KVS{
-		config.KV{
-			Key:   config.State,
-			Value: config.StateOn,
-		},
 		config.KV{
 			Key:   Drives,
 			Value: strings.Join(cfg.Drives, cacheDelimiter),