message: Updated Config.md document
diff: @@ -44,6 +44,7 @@ This function accepts a `config` parameter that defines the behavior of the clie
  "preordered_nodes": array<string> - (optional), names of nodes which will have priority during request sending.
  This can be useful if a user prefers querying specific nodes.
  Note: Nodes not specified will be placed randomly.
  + "number_read_nodes": int (optional) - the number of nodes to send read requests (2 by default)
  }
  ```
  