function switchtab(tab, toonAanpassen) {
	for (i=0;i<document.getElementById('tabs').childNodes.length;i++) {
		document.getElementById('tabs').childNodes[i].className = "";
	}
	for (i=0;i<document.getElementById('pages').childNodes.length;i++) {
		document.getElementById('pages').childNodes[i].className = "hidden";
	}
	if (toonAanpassen) document.getElementById('Aanpassen').className = "aanpassen"; 
	document.getElementById(tab).className = "selected";
	document.getElementById(tab + 'Tab').className = "selected";
}