SelColor()     Changes the color of an Object using the standard Dialog Box
 -------------------------------------------------------------------------------

   <oObject>:SelColor( <lFore> )   --> nil


 <oObject>       Is the Object to change colors for. This method is
                 implemented at TWindow Class, so any Window or any Object
                 which Class inherits from TWindow may use this method.

 <lFore>         Selects the Fore or the Back color of the Object to
                 be edited. By default is false, so it will edit the
                 Back color.

  This method automatically calls the Window standard Color selection
  Dialog Box and assigns the result to the oObject.

  If the user selects cancel, the Object keeps its previous color.