Add support for "windowbuttonmotionfcn" and "currentpoint" * Figure.cc (Figure::Figure): Enable mouse tracking if windowbuttonmotionfcn callback is defined. (Figure::update): Enable mouse tracking on canvas and all child widgets when windowbuttonmotionfcn is defined. * Panel.cc (Panel::Panel): Propagate mouse tracking to child widgets during initialization. * Container.h (Container::childEvent): New method. * Container.cc (Container::childEvent): Likewise. Propagate mouse tracking status to child widgets. * BaseControl.cc (BaseControl::eventFilter): Handle mouse move events and call figure's appropriate callback. * Canvas.h (Canvas::updateCurrentPoint): New method. * Canvas.cc (Canvas::updateCurrentPoint): Likewise. Update figure and child axes currentpoint property. (Canvas::canvasMouseMoveEvent): Update currentpoint properties and call windowbuttonmotionfcn callback. (Canvas::canvasMousePressEvent): Call updateCurrentPoint. (Canvas::canvasMouseReleaseEvent): Likewise.

gnulib-hg = gnulib-hg