Add upgrade file

Author: duncte123

README.md

@@ -71,7 +71,7 @@ jda.getDirectAudioController().connect(voiceChannel);
 
 > [!IMPORTANT]
 > Using `Guild#getAudioManager()` will ***NOT*** work. This is because the audio manager makes **JDA** connect to the voice channel, and we want to send the even to LavaLink.
-> You can however use `Member#getVoiceState` perfectly fine
+> You can however use `Member#getVoiceState` perfectly fine, this is also how you get the voice channel that your bot is in.
 
 ## Installation and usage with Discord4j
 

upgrade.md

@@ -0,0 +1,19 @@
+# Coming from the v3 client
+
+First things first, there is no dependency on lavaplayer anymore. This means that all the track loading will have to be done via the server.
+This also means that the following classes no longer exist:
+- PlayerEventListenerAdapter
+
+This client also uses project reactor, their docs are over at https://projectreactor.io/docs
+
+## Classes that serve similar purposes
+- `Lavalink`/`JDALavalink` -> `LavalinkClient`
+- `Link`/`JDALink` -> `Link`
+- `Link.State` -> `LinkState`
+- `LavalinkSocket` -> `Node`
+- `LavalinkRestClient` -> `Node`
+- `LavalinkLoadBalancer` -> `DefaultLoadBalancer`
+- `PenaltyProvider` -> `IPenaltyProvider`
+- Any filters -> they are in `dev.arbjerg.lavalink.protocol.v4.Filters` class.
+
+If you are missing anything from here, feel free to let me know in the lavalink discord