function dropdown(menu) {
	chosen = menu.options[menu.selectedIndex].value;
	if (chosen != "0") {
		window.location = "/category.php?category=" + chosen;
	}
}
function dropdownextra(menu) {
	chosen = menu.options[menu.selectedIndex].value;
	if (chosen != "0") {
		window.location = "/" + chosen;
	}
}
function dropdownnavigation(menu, formulier) {
	chosen = menu.options[menu.selectedIndex].value;
	if (chosen != "0") {
		document[formulier].submit();
	}
}