close-button fix for macosx

src/gui/qt/gamelobbydialog/gamelobbydialogimpl.cpp

@@ -20,7 +20,10 @@
 gameLobbyDialogImpl::gameLobbyDialogImpl(QWidget *parent, ConfigFile *c)
  : QDialog(parent), myW(NULL), myConfig(c), mySession(NULL), currentGameName(""), myPlayerId(0), isAdmin(false), inGame(false), myChat(NULL), keyUpCounter(0)
 {
-    setupUi(this);
+
+	setWindowModality(Qt::ApplicationModal);
+	setWindowFlags(Qt::WindowSystemMenuHint | Qt::CustomizeWindowHint | Qt::Dialog);
+    	setupUi(this);
 	
 	myChat = new LobbyChat(this, myConfig);