admin: Better production config for FoodTruck, provide proper first site. * Use a `settings` object to configure Flask. * Accept an `app.cfg` file in the admin folder to configure Flask. * Get a proper first site name when the cookie isn't set yet.

{% extends "section-page.html" %}

{% block header %}
<header class="code">
    <h1>{{ page.title }}</h1>
</header>
{% endblock %}