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.

migrations/Version20170510082609.php

@@ -0,0 +1,37 @@
+<?php
+
+namespace DoctrineMigrations;
+
+use App\Doctrine\WallabagMigration;
+use Doctrine\DBAL\Schema\Schema;
+
+/**
+ * Changed length for username, username_canonical, email and email_canonical fields in wallabag_user table.
+ */
+class Version20170510082609 extends WallabagMigration
+{
+    private $fields = [
+        'username',
+        'username_canonical',
+        'email',
+        'email_canonical',
+    ];
+
+    public function up(Schema $schema): void
+    {
+        $this->skipIf('mysql' !== $this->connection->getDatabasePlatform()->getName(), 'This migration only apply to MySQL');
+
+        foreach ($this->fields as $field) {
+            $this->addSql('ALTER TABLE ' . $this->getTable('user') . ' CHANGE ' . $field . ' ' . $field . ' VARCHAR(180) NOT NULL;');
+        }
+    }
+
+    public function down(Schema $schema): void
+    {
+        $this->skipIf('mysql' !== $this->connection->getDatabasePlatform()->getName(), 'This migration only apply to MySQL');
+
+        foreach ($this->fields as $field) {
+            $this->addSql('ALTER TABLE ' . $this->getTable('user') . ' CHANGE ' . $field . ' ' . $field . ' VARCHAR(255) NOT NULL;');
+        }
+    }
+}