Sets the group icon for the wizard plugin to the inputed icon.
        
        :param      groupName | <str>
                    icon      | <str>

def setGroupIcon( cls, groupName, icon ):
        """
        Sets the group icon for the wizard plugin to the inputed icon.
        
        :param      groupName | <str>
                    icon      | <str>
        """
        if ( cls._groupIcons is None ):
            cls._groupIcons = {}
            
        cls._groupIcons[nativestring(groupName)] = icon