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/fixtures/readability.json

@@ -0,0 +1,29 @@
+{
+  "bookmarks": [
+    {
+      "article__excerpt": "When Twitter started it had so much promise to change the way we communicate. But now it has been ruined by the amount of garbage and hate we have to wade through. It’s like that polluted…",
+      "favorite": false,
+      "date_archived": null,
+      "article__url": "https://venngage.com/blog/hashtags-are-worthless/",
+      "date_added": "2016-08-25T12:05:00",
+      "date_favorited": null,
+      "article__title": "We Looked At 167,943 Tweets & Found Out Hashtags Are Worthless",
+      "archive": false
+    },
+    {
+      "article__title": "No title found",
+      "article__url": "http://news.nationalgeographic.com/2016/02/160211-albatrosses-mothers-babies-animals-science/&sf20739758=1",
+      "archive": false,
+      "date_added": "2016-09-08T11:55:58+0200",
+      "favorite": true
+    },
+    {
+      "archive": 0,
+      "date_added": "2016-09-08T11:55:58+0200",
+      "favorite": 0,
+      "article__title": "Bordeaux: Poche, chocolatine… Une association traduit aux étudiants étrangers les mots du Sud-Ouest",
+      "article__url": "https://www.20minutes.fr/bordeaux/2120479-20170823-bordeaux-poche-chocolatine-association-traduit-etudiants-etrangers-mots-sud-ouest"
+    }
+  ],
+  "recommendations": []
+}