v2 README changes. (#462)

* v2 preview.

* update.

* Update README.md

Author: cloudwebrtc

README.md

@@ -14,6 +14,11 @@
 
 <!--BEGIN_DESCRIPTION-->
 Use this SDK to add real-time video, audio and data features to your Flutter app. By connecting to a self- or cloud-hosted <a href="https://livekit.io/">LiveKit</a> server, you can quickly build applications like interactive live streaming or video calls with just a few lines of code.
+
+## NOTE
+
+Version 2 of the <platform> SDK contains a small set of breaking changes. Read the [migration guide](https://docs.livekit.io/guides/migrate-from-v1/) for a detailed overview of what has changed.
+
 <!--END_DESCRIPTION-->
 
 This package is published to pub.dev as [livekit_client](https://pub.dev/packages/livekit_client).
@@ -42,6 +47,8 @@ More Docs and guides are available at [https://docs.livekit.io](https://docs.liv
 
 We built a multi-user conferencing app as an example in the [example/](example/) folder. You can join the same room from any supported LiveKit clients.
 
+Online demo: https://livekit.github.io/client-sdk-flutter/
+
 ## Installation
 
 Include this package to your `pubspec.yaml`
@@ -182,12 +189,6 @@ Note: the audio routing will become controlled by the system and cannot be manua
 
 In order to enable Flutter desktop development, please follow [instructions here](https://docs.flutter.dev/desktop#set-up).
 
-On M1 Macs, you will also need to install x86_64 version of FFI:
-
-```
-sudo arch -x86_64 gem install ffi
-```
-
 On Windows [VS 2019](https://visualstudio.microsoft.com/thank-you-downloading-visual-studio/?sku=community&rel=16) is needed (link in flutter docs will download VS 2022).
 
 ## Usage
@@ -201,7 +202,10 @@ final roomOptions = RoomOptions(
   // ... your room options
 )
 
-final room = await LiveKitClient.connect(url, token, roomOptions: roomOptions);
+final room = Room();
+
+await room.connect(url, token, roomOptions: roomOptions);
+
 try {
   // video will fail when running in ios simulator
   await room.localParticipant.setCameraEnabled(true);