Memory leak von Shop Client behoben

KSGClient/NachLogin/Shop/Karten/KartenKaufen.cpp

@@ -617,7 +617,8 @@ void KartenKaufenListe::ladeKarten( Array< int > *karten )
 {
     leeren();
     int anz = karten->getEintragAnzahl();
-    shopClient = mainClient->createShopServerClient();
+    if( !shopClient )
+        shopClient = mainClient->createShopServerClient();
     if( shopClient && shopClient->verbinde() )
     {
         for( int i = 0; i < anz; i++ )