assert response body based on spec examples

spec/dummy/db/migrate/20160218212104_create_blogs.rb

@@ -0,0 +1,10 @@
+class CreateBlogs < ActiveRecord::Migration
+  def change
+    create_table :blogs do |t|
+      t.string :title
+      t.text :content
+
+      t.timestamps
+    end
+  end
+end