message: Update `known_addresses` in README.md
diff: @@ -56,12 +56,13 @@ default values otherwise. For example:
  cargo run --release -- validator resources/local/config.toml -C=consensus.secret_key_path=secret_keys/node-1.pem
  ```
  -Note that `network.known_address` must refer to a public listening address of a currently-running node. If the node
  -cannot connect to this address, it will panic. The node _can_ be run with this referring to its own address, but it
  -will be equivalent to not specifying any value for `known_address` - i.e. the node will run and listen, but will be
  -reliant on other nodes connecting to it in order to join the network. This would be normal for the very first node of a
  -network, but all subsequent nodes should normally specify that first node's public listening address as their
  -`known_address`.
  +Note that `network.known_addresses` must refer to public listening addresses of one or more
  +currently-running nodes. If the node cannot connect to any of these addresses, it will panic. The
  +node _can_ be run with this referring to its own address, but it will be equivalent to specifying an
  +empty list for `known_addresses` - i.e. the node will run and listen, but will be reliant on other
  +nodes connecting to it in order to join the network. This would be normal for the very first node
  +of a network, but all subsequent nodes should normally specify that first node's public listening
  +address as their `known_addresses`.
  As well as the commented [local config file](resources/local/config.toml), there is a commented
  [local chainspec](resources/local/chainspec.toml) in the same folder.
  