avoid shadowed variable warnings in libgui sources * BaseControl.cc, BaseControl.h, Container.cc, ContextMenu.cc, Figure.cc, FigureWindow.cc, GLCanvas.cc, GenericEventNotify.h, Menu.cc, MouseModeActionGroup.cc, Panel.cc, TextEdit.cc, TextEdit.h, ToolBar.cc: Rename local variables to avoid shadowing class members or functions.

#include <octave/oct.h>

DEFUN_DLD (helloworld, args, nargout,
           "Hello World Help String")
{
  int nargin = args.length ();

  octave_stdout << "Hello World has "
                << nargin << " input arguments and "
                << nargout << " output arguments.\n";

  return octave_value_list ();
}