even in the code you pasted above, you have still not made the change I am asking you to make, you still have the data format using the wrong syntax:
$('#Dateofbirth').datepicker({
Dateformat: 'yy-mm-dd',
it should be:
$('#Dateofbirth').datepicker({
dateFormat: 'yy-mm-dd',
note the use of lower case "d" and upper case "F" in "dateFormat"