#31 Dragged objects should use the middle of the object as drawing anchor instead of the upper left corner

When an object is dragged from the left panel, the floating image of the object is drawn taking the upper left corner of the image as the anchor. However, objects rendered on the canvas use the middle point of the image as the anchor point for drawing them. This causes that when a user drops an object into the canvas, the object is not dropped into the expected position. Instead, when dropped, an object moves slightly upwards and to the left. Please leave a comment if this issue is not clear (it was tricky to describe).