Add GameModel and lastPlayedCard

src/main/java/de/hsfulda/onses/models/Game.java

@@ -0,0 +1,15 @@
+package de.hsfulda.onses.models;
+
+public class Game {
+
+    private Card lastPlayedCard = null;
+
+    public Card getLastPlayedCard() {
+        return lastPlayedCard;
+    }
+
+    public Game setLastPlayedCard(Card lastPlayedCard) {
+        this.lastPlayedCard = lastPlayedCard;
+        return this;
+    }
+}