diff.c: --no-color to defeat diff.color configuration.

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff.c

@@ -1625,6 +1625,8 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 	}
 	else if (!strcmp(arg, "--color"))
 		options->color_diff = 1;
+	else if (!strcmp(arg, "--no-color"))
+		options->color_diff = 0;
 	else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
 		options->xdl_opts |= XDF_IGNORE_WHITESPACE;
 	else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))