FEATURE #1337: add file upload

This commit registers new items into admin menu and adds functionality for uploading files.

app/Events/UploadFile.php

@@ -0,0 +1,42 @@
+<?php
+
+namespace App\Events;
+
+use Illuminate\Queue\SerializesModels;
+use Symfony\Component\HttpFoundation\File\File;
+use Symfony\Component\HttpFoundation\File\UploadedFile;
+
+class UploadFile extends Event
+{
+    use SerializesModels;
+    /**
+     * @var UploadedFile
+     */
+    private $uploadedFile;
+    /**
+     * @var
+     */
+    private $id;
+
+    /**
+     * Create a new event instance.
+     *
+     * @param File $uploadedFile
+     * @param      $id
+     */
+    public function __construct(File $uploadedFile, $id)
+    {
+        $this->uploadedFile = $uploadedFile;
+        $this->id = $id;
+    }
+
+    /**
+     * Get the channels the event should be broadcast on.
+     *
+     * @return array
+     */
+    public function broadcastOn()
+    {
+        return [];
+    }
+}