Use platform agnostic example in README.md (#223)

Co-authored-by: Nate Bosch <nbosch@google.com>
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5b559ef..1c5b128 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 2.2.1-dev
+
+- Use platform agnostic code in README example.
+
 ## 2.2.0
 
 - Add `HtmlWebSocketChannel.innerWebSocket` getter to access features not exposed
diff --git a/README.md b/README.md
index ca30950..5658ecc 100644
--- a/README.md
+++ b/README.md
@@ -20,11 +20,12 @@
 [status]: https://pub.dev/documentation/web_socket_channel/latest/status/status-library.html
 
 ```dart
-import 'package:web_socket_channel/io.dart';
+import 'package:web_socket_channel/web_socket_channel.dart';
 import 'package:web_socket_channel/status.dart' as status;
 
 main() async {
-  var channel = IOWebSocketChannel.connect(Uri.parse('ws://localhost:1234'));
+  final wsUrl = Uri.parse('ws://localhost:1234')
+  var channel = WebSocketChannel.connect(wsUrl);
 
   channel.stream.listen((message) {
     channel.sink.add('received!');
diff --git a/pubspec.yaml b/pubspec.yaml
index 1f42871..4c83080 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: web_socket_channel
-version: 2.2.0
+version: 2.2.1-dev
 
 description: >-
   StreamChannel wrappers for WebSockets. Provides a cross-platform