Use matrix concatenation for strings, rather than cstrcat(), for clarity and performance. matrix concatenation is ~80% faster than cstrcat(). * doc/interpreter/strings.txi: Document preference for matrix concatenation as opposed to alternatives. * doc/interpreter/geometryimages.m, doc/interpreter/interpimages.m, doc/interpreter/plotimages.m, doc/interpreter/sparseimages.m, doc/interpreter/splineimages.m, scripts/general/genvarname.m, scripts/general/int2str.m, scripts/general/num2str.m, scripts/help/__makeinfo__.m, scripts/help/help.m, scripts/miscellaneous/copyfile.m, scripts/miscellaneous/dir.m, scripts/miscellaneous/edit.m, scripts/miscellaneous/fact.m, scripts/miscellaneous/fullfile.m, scripts/miscellaneous/mkoctfile.m, scripts/miscellaneous/movefile.m, scripts/miscellaneous/perl.m, scripts/miscellaneous/python.m, scripts/miscellaneous/run.m, scripts/miscellaneous/tempdir.m, scripts/miscellaneous/unpack.m, scripts/pkg/private/configure_make.m, scripts/pkg/private/create_pkgadddel.m, scripts/pkg/private/extract_pkg.m, scripts/pkg/private/get_description.m, scripts/pkg/private/get_forge_pkg.m, scripts/pkg/private/getarch.m, scripts/pkg/private/getarchprefix.m, scripts/pkg/private/install.m, scripts/pkg/private/installed_packages.m, scripts/pkg/private/load_packages_and_dependencies.m, scripts/pkg/private/rebuild.m, scripts/pkg/private/repackage.m, scripts/pkg/private/shell.m, scripts/pkg/private/uninstall.m, scripts/plot/private/__go_draw_axes__.m, scripts/signal/spectral_adf.m, scripts/signal/spectral_xdf.m, scripts/statistics/tests/z_test.m, scripts/statistics/tests/z_test_2.m, scripts/strings/mat2str.m, scripts/strings/strtok.m, scripts/testfun/__run_test_suite__.m, scripts/testfun/assert.m, scripts/testfun/demo.m, scripts/testfun/speed.m, scripts/testfun/test.m, test/eval-catch.tst, test/io.tst, test/try.tst: Replace cstrcat() with matrix concatenation where possible.

--- a/scripts/miscellaneous/unpack.m
+++ b/scripts/miscellaneous/unpack.m
@@ -78,7 +78,7 @@
       [tmppathstr, tmpname, tmpext] = fileparts (name);
       if (strcmpi (tmpext, ".tar"))
         name = tmpname;
-        ext = cstrcat (tmpext, ext);
+        ext = [tmpext ext];
       endif
     endif
 
@@ -88,7 +88,7 @@
       urlfile = file;
       ## FIXME -- should we name the file that we download with the
       ## same file name as the URL requests?
-      tmpfile = cstrcat (tmpnam (), ext);
+      tmpfile = [tmpnam() ext];
       [file, success, msg] = urlwrite (urlfile, tmpfile);
       if (! success)
         error ("unpack: could not get \"%s\": %s", urlfile, msg);
@@ -178,7 +178,7 @@
 
   unwind_protect
     cd (dir);
-    [status, output] = system (sprintf (cstrcat (command, " 2>&1"), file));
+    [status, output] = system (sprintf ([command " 2>&1"], file));
   unwind_protect_cleanup
     cd (origdir);
   end_unwind_protect