Separated laravel app to its own folder (#540)

api/app/Providers/PurifySetupProvider.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace App\Providers;
+
+use App\Service\HtmlPurifier\HTMLPurifier_URIScheme_notion;
+use Illuminate\Support\ServiceProvider;
+
+class PurifySetupProvider extends ServiceProvider
+{
+    /**
+     * Bootstrap services.
+     *
+     * @return void
+     */
+    public function boot()
+    {
+        \HTMLPurifier_URISchemeRegistry::instance()->register('notion', new HTMLPurifier_URIScheme_notion());
+    }
+}