FEATURE #1337: add file upload

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

app/Http/Requests/UploadFileRequest.php

@@ -2,17 +2,13 @@
 
 namespace App\Http\Requests;
 
-class UploadFileRequest extends Request
+class UploadFileRequest extends UploadRequest
 {
     /**
-     * Get the validation rules that apply to the request.
-     *
-     * @return array
+     * @internal param array $rules
      */
-    public function rules()
+    protected function setRules()
     {
-        return [
-            'file' => 'required'
-        ];
+        $this->rules = ['file' => 'required|image'];
     }
 }