Include error pages

website/thaliawebsite/templates/400.html

+{% extends "error.html" %}
+{% load i18n %}
+
+{% block error_message %}{% trans "400: Bad request" %}{% endblock %}

website/thaliawebsite/templates/403.html

+{% extends "error.html" %}
+{% load i18n %}
+
+{% block error_message %}{% trans "403: Permision denied." %}<br>
+
+{{ exception }}
+{% endblock %}

website/thaliawebsite/templates/404.html

+{% extends "error.html" %}
+{% load i18n %}
+
+{% block error_message %}{% trans "404: page not found." %}<br>
+<!-- {{ exception }} -->
+{% endblock %}

website/thaliawebsite/templates/500.html

+{% extends "error.html" %}
+{% load i18n %}
+
+{% block error_message %}{% trans "500: internal server error. Thalia's website committee has been notified." %}{% endblock %}

website/thaliawebsite/templates/error.html

+{% extends 'base.html' %}
+{% load i18n %}
+
+{% block title %}Error — {{ block.super }}{% endblock %}
+
+{% block page_title %}{% trans "Error" %}{% endblock %}
+
+{% block body %}
+<h1>{% blocktrans %}Error{% endblocktrans %}</h1>
+
+<p>
+    {% block error_message %}{% trans "An error occurred." %}{% endblock %}
+</p>
+
+<iframe width="560" height="315" src="https://www.youtube.com/embed/t3otBjVZzT0?autoplay=0" frameborder="0" allowfullscreen></iframe>
+
+{% endblock %}