CHANGELOG
=========
4.2.0
-----
* [BC BREAK] `MessageSubscriberInterface::getHandledMessages()` return value has changed. The value of an array item
needs to be an associative array or the method name.
* `ValidationMiddleware::handle()` and `SendMessageMiddleware::handle()` now require an `Envelope` object
* `EnvelopeItemInterface` doesn't extend `Serializable` anymore
* [BC BREAK] The `ConsumeMessagesCommand` class now takes an instance of `Psr\Container\ContainerInterface`
as first constructor argument
