Feature: Add ArrayAssembler

[gitlog]

Implementation of IteratorAggregate (https://www.php.net/manual/ru/class.iteratoraggregate.php), ArrayAccess (https://www.php.net/manual/ru/class.arrayaccess.php), Countable (https://www.php.net/manual/ru/class.countable.php) interfaces to provide accessing objects as arrays. When we has generated class with IteratorAssembler - we can to add only one element to this array. To add more elements, must use ArrayAccess interface. With Countable interface will be available element's counting, with IteratorAggregate - iterating array elements in loop.