Make some graphics factory defaults conform to Matlab values (bug #41770). * graphics.in.h: add "diplayname" property to image objects. * graphics.in.h: correct factory values of 'textmargin', 'surfacefacelighting', 'surfacexdata', 'surfaceydata', 'surfacezdata', 'surfacealphadata', 'surfacecdata', 'patchvertices', 'patchspecularstrength', 'patchfaces', 'imagealphadata', 'imagealphadatamapping', 'imagecdata', 'axesview', 'axescameraupvector'. * graphics.cc: create new static functions default_surface_xdata (void), default_surface_ydata (void), default_surface_zdata (void), default_surface_cdata (void), default_patch_faces (void), default_patch_vertices (void), default_axes_view (void), default_image_cdata (void) * libinterp/corefcn/octave-default-image.h: New file

gnulib-hg = gnulib-hg