Move to Symfony Flex

The structure changed completely.
Bundles are gone. Everything is flatten in the folder `src`.
I separated import & api controllers to avoid _pollution_ in the main controller folder.

tests/Controller/StaticControllerTest.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace App\Tests\Controller;
+
+use App\Tests\WallabagCoreTestCase;
+
+class StaticControllerTest extends WallabagCoreTestCase
+{
+    public function testAbout()
+    {
+        $this->logInAs('admin');
+        $client = $this->getTestClient();
+
+        $client->request('GET', '/about');
+
+        $this->assertSame(200, $client->getResponse()->getStatusCode());
+    }
+
+    public function testHowto()
+    {
+        $this->logInAs('admin');
+        $client = $this->getTestClient();
+
+        $client->request('GET', '/howto');
+
+        $this->assertSame(200, $client->getResponse()->getStatusCode());
+    }
+}