GH-992 Add a transaction/locking mechanism to settings objects

This can cut the FTB loading by ~66% - worth it, but not ideal.
Real solution will have to be implemented later.

application/pages/InstanceSettingsPage.h

@@ -69,6 +69,6 @@ private slots:
 private:
 	Ui::InstanceSettingsPage *ui;
 	BaseInstance *m_instance;
-	SettingsObject *m_settings;
+	SettingsObjectPtr m_settings;
 	QObjectPtr<JavaCommon::TestCheck> checker;
 };