Use upper/lower in preference to toupper/tolower to match Matlab. * mappers.cc (Fupper, Flower): Functions renamed from toupper/tolower and now use "DEFUN" macro. Change DEFALIAS to correctly map toXXX to XXX. Update all BIST tests. * func.txi, strings.txi: Update manual. * cellfun.cc, utils.cc, Map.m, idivide.m, integral.m, integral2.m, integral3.m, interp1.m, quad2d.m, quadgk.m, rng.m, griddata.m, griddatan.m, listdlg.m, movegui.m, __file_filter__.m, uigetfile.m, uisetfont.m, __unimplemented__.m, colormap.m, imformats.m, imshow.m, __imread__.m, __imwrite__.m, rgbplot.m, javaclasspath.m, genvarname.m, edit.m, inputParser.m, license.m, open.m, parseparams.m, unpack.m, validateattributes.m, __all_opts__.m, get_description.m, get_forge_pkg.m, camorbit.m, daspect.m, datetick.m, pbaspect.m, __tickangle__.m, rticks.m, thetaticks.m, xticks.m, yticks.m, zticks.m, camlight.m, colorbar.m, isocaps.m, isosurface.m, __add_datasource__.m, __patch__.m, __scatter__.m, reducepatch.m, smooth3.m, surfl.m, hgload.m, hold.m, openfig.m, __add_default_menu__.m, __print_parse_opts__.m, refreshdata.m, saveas.m, struct2hdl.m, movfun.m, stft.m, eigs.m, ichol.m, ilu.m, gammainc.m, gallery.m, corrcoef.m, iqr.m, normalize.m, base2dec.m, index.m, regexptranslate.m, strsplit.m, datestr.m, mk-sparse-tst.sh: Replace toupper/tolower with upper/lower in Octave code.

--- a/scripts/plot/draw/private/__add_datasource__.m	Wed Apr 12 14:40:52 2023 -0700
+++ b/scripts/plot/draw/private/__add_datasource__.m	Wed Apr 12 15:34:43 2023 -0700
@@ -44,7 +44,7 @@
     arg = varargin{++i};
     if (i != numel (varargin) && ischar (arg)
         && length (arg) > 9 && strcmpi (arg(end-9:end), "datasource"))
-      arg = tolower (arg);
+      arg = lower (arg);
       val = varargin{++i};
       if (ischar (val))
         set (h, arg, val);