Re: [PATCH v3 02/11] i18n: refactor "%s, %s and %s are mutually exclusive"

"Jean-Noël Avila via GitGitGadget"  [off-list ref] writes:

 	if (use_stdout + rev.diffopt.close_file + !!output_directory > 1)
-		die(_("--stdout, --output, and --output-directory are mutually exclusive"));
+		die(_("options '%s', '%s' and '%s' cannot be used together"), "--stdout", "--output", "--output-directory");

We probably want to preserve the Oxford comma here, and unify the
ones that didn't use Oxford comma to use it.