Add server deletion to a queue.

This action allows servers to be deleted, but only be soft-deleted for
10 minutes. After that time period the server will be completely
removed from the database and daemon. This allows some safety if a
server is accidentally deleted.

Force deleting a server will still work. If the daemon is in-accessible
the server will fail to be deleted. When server is soft-deleted admins
can still view its information page in the admin CP, however the server
will be suspended and inaccessible on the front-end or though the
daemon.

Admins can manually delete the server ahead of the delete timer, or if
it failed to delete previously they can do an immediate retry.

app/Listeners/DeleteServerListener.php

@@ -0,0 +1,64 @@
+<?php
+/**
+ * Pterodactyl - Panel
+ * Copyright (c) 2015 - 2016 Dane Everitt <dane@daneeveritt.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+namespace Pterodactyl\Listeners;
+
+use Carbon;
+
+use Pterodactyl\Events\ServerDeleted;
+use Illuminate\Foundation\Bus\DispatchesJobs;
+
+use Pterodactyl\Jobs\SuspendServer;
+use Pterodactyl\Jobs\DeleteServer;
+
+class DeleteServerListener
+{
+
+    use DispatchesJobs;
+
+    /**
+     * Create the event listener.
+     *
+     * @return void
+     */
+    public function __construct()
+    {
+        //
+    }
+
+    /**
+     * Handle the event.
+     *
+     * @param  DeleteServerEvent  $event
+     * @return void
+     */
+    public function handle(ServerDeleted $event)
+    {
+        $this->dispatch((new SuspendServer($event->server))->onQueue(env('QUEUE_HIGH', 'high')));
+        $this->dispatch(
+            (new DeleteServer($event->server))
+            ->delay(Carbon::now()->addMinutes(env('APP_DELETE_MINUTES', 10)))
+            ->onQueue(env('QUEUE_STANDARD', 'standard'))
+        );
+    }
+}