sub add_gff_track {
	my ( $browser_project_dir, $gff_file, $track_label, $key, @optional_args )
		= @_;
	my @args = (
		"bin/flatfile-to-json.pl", "--gff=$gff_file",
		"--tracklabel=$track_label", "--key=$key", @optional_args
	);
	chdir_and_system( $browser_project_dir, @args );

}