[5.0] Allow composer require illuminate/routing without extra illuminate/events

[Marwelln]

If we are trying to use illuminate/routing, we are required to manually require illuminate/events as it's used in the __construct method of Illuminate\Routing\Router.php. This change will allow us to only require illuminate/routing if we want to use the routing system without the main Laravel framework.

[GrahamCampbell]

Not it's not. We're asking for a contract. Please could you add this to the suggested dependencies list though, in the same format we do for the other suggestions in packages.

[crynobone]

@GrahamCampbell but it would be useful if we can suggest an implementation using composer suggest.

[GrahamCampbell]

@crynobone That's what I meant when I said:

Please could you add this to the suggested dependencies list though, in the same format we do for the other suggestions in packages.

[crynobone]

@GrahanCampbell missed that.

@Marwelln service provider are designed to be use in Laravel. For external project you should manage configuring the service on your own, which include setting up an implementation of Illuminate\Contracts\Events\Dispatcher.