VISULIST or VisualList

A linked list derived from linklist.cpp to manipulate objects derived from objectclass
(see object.h) using the approtriate objectcontrolclass (again see object.h)

  VisualLinkClass* VisualListClass::Add(ObjectControlClass* control,
                                           int x, int y, int w, int h)
    Called from edit3d.cpp to create an object. Parameter x,y,w,h are the objects
    position and size.  Note: An object also has parameters PosLocked and SizeLocked,
    which are by default false but, in the case of a Vertex, SizeLocked is set true.
    This will prevent any attempt to resize a Vertex which would make little sense.
