* Add `#[AsEventListener]` attribute for declaring listeners on PHP 8
5.1.0
-----
* The `LegacyEventDispatcherProxy` class has been deprecated.
* Added an optional `dispatcher` attribute to the listener and subscriber tags in `RegisterListenerPass`.
5.0.0
-----
* The signature of the `EventDispatcherInterface::dispatch()` method has been changed to `dispatch($event, string $eventName = null): object`.
* The `Event` class has been removed in favor of `Symfony\Contracts\EventDispatcher\Event`.
* The `TraceableEventDispatcherInterface` has been removed.
* The `WrappedListener` class is now final.
4.4.0
-----
*`AddEventAliasesPass` has been added, allowing applications and bundles to extend the event alias mapping used by `RegisterListenersPass`.
* Made the `event` attribute of the `kernel.event_listener` tag optional for FQCN events.
4.3.0
-----
* The signature of the `EventDispatcherInterface::dispatch()` method should be updated to `dispatch($event, string $eventName = null)`, not doing so is deprecated
* deprecated the `Event` class, use `Symfony\Contracts\EventDispatcher\Event` instead
4.1.0
-----
* added support for invokable event listeners tagged with `kernel.event_listener` by default
* The `TraceableEventDispatcher::getOrphanedEvents()` method has been added.
* The `TraceableEventDispatcherInterface` has been deprecated.
4.0.0
-----
* removed the `ContainerAwareEventDispatcher` class
* added the `reset()` method to the `TraceableEventDispatcherInterface`
3.4.0
-----
* Implementing `TraceableEventDispatcherInterface` without the `reset()` method has been deprecated.
3.3.0
-----
* The ContainerAwareEventDispatcher class has been deprecated. Use EventDispatcher with closure factories instead.
3.0.0
-----
* The method `getListenerPriority($eventName, $listener)` has been added to the
`EventDispatcherInterface`.
* The methods `Event::setDispatcher()`, `Event::getDispatcher()`, `Event::setName()`
and `Event::getName()` have been removed.
The event dispatcher and the event name are passed to the listener call.
2.5.0
-----
* added Debug\TraceableEventDispatcher (originally in HttpKernel)
* changed Debug\TraceableEventDispatcherInterface to extend EventDispatcherInterface
* added RegisterListenersPass (originally in HttpKernel)
2.1.0
-----
* added TraceableEventDispatcherInterface
* added ContainerAwareEventDispatcher
* added a reference to the EventDispatcher on the Event
* added a reference to the Event name on the event
* added fluid interface to the dispatch() method which now returns the Event
object
* added GenericEvent event class
* added the possibility for subscribers to subscribe several times for the
