maximumSelectionLength not enforced with closeOnSelect: false

[realalex]

While I'd normally be more thorough with your reporting format, this one is pretty self-explanatory.

$('.select2').select2({
        closeOnSelect: false, 
        maximumSelectionLength: 4
});

When closeOnSelect is false, the users have free reign to select as many options as they want. closeOnSelect: true solves the issue, but it's totally unintuitive.

[kevin-brown]

This is a duplicate of #3514.