Enhance filter(Function) to pass index

[joern]

By passing the index as an argument to the filter callback, you could do something like this:

$(...).filter("id", function(i) {
  return "foobar" + i;
});

Can be quite useful (see mailing lis, "Update to 1.1 question" by Olaf Bosch) and should be very easy to implement.

[joern]

already supported