Change models, new migrations, fix front and make tests work

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

lib/eventos_web/views/category_view.ex

@@ -1,3 +1,19 @@
 defmodule EventosWeb.CategoryView do
   use EventosWeb, :view
+  alias EventosWeb.CategoryView
+
+  def render("index.json", %{categories: categories}) do
+    %{data: render_many(categories, CategoryView, "category.json")}
+  end
+
+  def render("show.json", %{category: category}) do
+    %{data: render_one(category, CategoryView, "category.json")}
+  end
+
+  def render("category.json", %{category: category}) do
+    %{id: category.id,
+      title: category.title,
+      description: category.description,
+      picture: category.picture}
+  end
 end