function change_header_photo() {
	var randomNumber=1 + Math.floor(Math.random()*20);
	document.header_photo.src="/images/header_photo_"+randomNumber+".png"
}

function importLink(link) {
    if (confirm("You are about to download an IMS content-package. This is meant for import in an ELO.")){
        document.location = link
    }
}

function confirmAndClick(confirmationText, link) {
    if (confirm(confirmationText)){
        document.location = link
    }
}