admin: Lots of fixes for running the admin panel in a WSGI server. - Use new source APIs in the dashboard to open WIP files. - Fixed broken/outdated code in some views. - Fixed cases when Flask is not running at the root URL by using the `SCRIPT_NAME` variable somewhat more properly.

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

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