feat(user-sessions): introduce GameLobby and GameUtil for session management and code generation

knockoutwhistweb/app/model/game/GameLobby.scala

@@ -0,0 +1,14 @@
+package model.game
+
+import de.knockoutwhist.control.GameLogic
+import de.knockoutwhist.utils.events.{EventListener, SimpleEvent}
+
+class GameLobby(val logic: GameLogic) extends EventListener{
+  logic.addListener(this)
+  logic.createSession()
+
+
+  override def listen(event: SimpleEvent): Unit = {
+    
+  }
+}