function PopupCentrer(page,largeur,hauteur,options)
{
  var top=(screen.height-hauteur)/2;
  var left=(screen.width-largeur)/2;
  window.open(page,"","top="+top+",left="+left+",width="+largeur+",height="+hauteur+","+options);
}

function cligno(id_elt)
{
	if(document.getElementById(id_elt).style.visibility != 'hidden')
	{
		document.getElementById(id_elt).style.visibility = 'hidden';
	}
	else
	{
		document.getElementById(id_elt).style.visibility = 'visible';
	}
}