feat: implemented partial RoundTimer

Server/src/main/java/uulm/teamname/marvelous/server/lobby/RoundTimer.java

@@ -0,0 +1,30 @@
+package uulm.teamname.marvelous.server.lobby;
+
+import uulm.teamname.marvelous.server.ParticipantType;
+import uulm.teamname.marvelous.server.lobbymanager.Participant;
+
+import java.util.Timer;
+import java.util.TimerTask;
+
+public class RoundTimer {
+    private final Timer timer;
+    private final Lobby parent;
+    private final int time;
+
+    public RoundTimer(int maxRoundTime, Lobby parent) {
+        this.timer = new Timer();
+        time = maxRoundTime;
+        this.parent = parent;
+    }
+
+    public void startRoundTimer(Participant p) {
+        if (p.type == ParticipantType.Spectator) throw new IllegalStateException("Spectators don't have TurnTime");
+        timer.cancel();
+//        timer.schedule(new TimerTask() {
+//            @Override
+//            public void run() {
+//                // TODO: skip current round
+//            }
+//        });
+    }
+}