Fix app event service provider contract

app/Providers/EventServiceProvider.php

 <?php namespace App\Providers;
 
+use Illuminate\Contracts\Events\Dispatcher as DispatcherContract;
 use Illuminate\Foundation\Support\Providers\EventServiceProvider as ServiceProvider;
 
 class EventServiceProvider extends ServiceProvider {
@@ -18,9 +19,10 @@ class EventServiceProvider extends ServiceProvider {
 	/**
 	 * Register any other events for your application.
 	 *
+	 * @param  \Illuminate\Contracts\Events\Dispatcher  $events
 	 * @return void
 	 */
-	public function boot()
+	public function boot(DispatcherContract $events)
 	{
 		//
 	}