Add shift to the other drag types

Shift is only used in bone mode for the pelvis and spine parts.

Previously the arm and leg drag points would be present even though
shift doesn't do anything different for them.

COM3D2.MeidoPhotoStudio.Plugin/MeidoPhotoStudio/DragPoint/DragPoint.cs

@@ -169,7 +169,8 @@ namespace COM3D2.MeidoPhotoStudio.Plugin
         {
             return InputManager.GetKey(MpsKey.DragSelect) || InputManager.GetKey(MpsKey.DragDelete)
                 || InputManager.GetKey(MpsKey.DragMove) || InputManager.GetKey(MpsKey.DragRotate)
-                || InputManager.GetKey(MpsKey.DragScale) || InputManager.GetKey(MpsKey.DragFinger);
+                || InputManager.GetKey(MpsKey.DragScale) || InputManager.GetKey(MpsKey.DragFinger)
+                || InputManager.Shift;
         }
 
         protected Vector3 CursorPosition()