save rotate_on_terrain checkbox state

src/noggit/MapView.cpp

@@ -849,6 +849,9 @@ void MapView::setupScriptingUi()
 
 void MapView::setupObjectEditorUi()
 {
+  // initialize some saved defaults
+  _object_paste_params.rotate_on_terrain = _settings->value("paste_params/rotate_on_terrain", true).toBool();
+
   /* Tool */
   objectEditor = new Noggit::Ui::object_editor(this
     , _world.get()

src/noggit/ui/ObjectEditor.cpp

@@ -481,6 +481,8 @@ namespace Noggit
       connect(paste_override_rotate_cb, &QCheckBox::stateChanged, [=](int s)
           {
               paste_params->rotate_on_terrain = s;
+              _settings->setValue("paste_params/rotate_on_terrain", (bool)s);
+              _settings->sync();
           });
 
       connect ( pasteModeGroup, qOverload<int> (&QButtonGroup::idClicked)