Add MODE, PRIVMSG, NOTICE server messages

Signed-off-by: observer <admin@shr4pnel.com>

src/main/kotlin/com/shr4pnel/ferretirc/net/messages/ServerMessage.kt

@@ -3,5 +3,8 @@ package com.shr4pnel.ferretirc.net.messages
 sealed class ServerMessage {
     class Cap() : ServerMessage()
     class Pong(val token: String? = null) : ServerMessage()
+    class Mode(val operatorName: String, val pMask: String): ServerMessage()
+    class PrivMsg(val targets: List<String>, message: String): ServerMessage()
+    class Notice(val targets: List<String>, message: String): ServerMessage()
     class UNIMPLEMENTED(val msg: String) : ServerMessage()
 }