make copying figures to clipboard work (bug #44866) * Figure.cc (Figure::copy_figure_callback): Just print the figure to a file here, then call octave_link::copy_image_to_clipboard. (delete_file): Delete unused static function. * main-window.h, main-window.cc (main_window::copy_image_to_clipboard): New function. (main_window::construct_octave_qt_link): Connect octave_qt_link::copy_image_to_clipboard_signal signal to main_window::copy_image_to_clipboard slot. * octave-qt-link.h, octave-qt-link.cc (octave_qt_link::do_copy_image_to_clipboard): New function. (octave_qt_link::copy_image_to_clipboard_signal): New signal. * octave-link.h (octave_link::do_copy_image_to_clipboard): New pure virtual function. (octave_link::copy_image_to_clipboard): New static funtion.

geometryimages.m voronoi triplot griddata convhull delaunay inpolygon
interpimages.m interpft interpn interpderiv1 interpderiv2
plotimages.m plot hist errorbar polar mesh plot3 extended
sparseimages.m gplot grid spmatrix spchol spcholperm
splineimages.m splinefit1 splinefit2 splinefit3 splinefit4 splinefit6