Gui: Gesture: add option to disable tilt

On Qt5, using pinch will inevitably cause tilt. It's annoying, so it is disabled by default.

In the future, it's best to introduce some kind of threshold to overcome for the tilt to be triggered.

src/Gui/DlgSettings3DViewImp.cpp

@@ -88,6 +88,7 @@ void DlgSettings3DViewImp::saveSettings()
 
     checkBoxZoomAtCursor->onSave();
     checkBoxInvertZoom->onSave();
+    checkBoxDisableTilt->onSave();
     spinBoxZoomStep->onSave();
     checkBoxDragAtCursor->onSave();
     CheckBox_CornerCoordSystem->onSave();
@@ -107,6 +108,7 @@ void DlgSettings3DViewImp::loadSettings()
 {
     checkBoxZoomAtCursor->onRestore();
     checkBoxInvertZoom->onRestore();
+    checkBoxDisableTilt->onRestore();
     spinBoxZoomStep->onRestore();
     checkBoxDragAtCursor->onRestore();
     CheckBox_CornerCoordSystem->onRestore();