Gets a SuperToolTip object for the current BarItemLink.
The type of tooltips, displayed for bar item links, is determined by a ToolTipController (by default, by the DefaultToolTipController). If the ToolTipController.ToolTipType property is set to SuperTip, SuperToolTips, rather than regular tooltips, are displayed for bar item links. If a regular tooltip is assigned to a bar item, it will be transformed into a SuperToolTip object and displayed onscreen.
The GetSuperTip method returns a SuperToolTip object that has been explicitly assigned to a bar item. If no SuperToolTip has been explicitly assigned, the method transforms the bar item's regular tooltip to a new SuperToolTip and then returns this object.