function vider(cible){
	target = document.getElementById(cible);
	if(target.value=="Email")
	{
		target.value = "";
	}
	else if(target.value=="password")
	{
		target.value = "";
	}
}
function login()
{
	if(document.getElementById('input_email').value == '' || document.getElementById('input_password').value == '')
	{
		alert('Veuillez renseigner vos identifiants');
	}
	else
	{
		document.getElementById('formu').submit();
	}
}