add a guide topics system

app/templates/guides/category_index.html

@@ -0,0 +1,15 @@
+{% extends 'base.html' %}
+{% block title %}guides - {{ category | title }}{% endblock %}
+{% block content %}
+<div class="darkbg settings-container">
+  <h1 class="thread-title">All guides in category "{{ category | replace('-', ' ') | title }}"</h1>
+  <ul>
+    {% for page in pages %}
+      <li><a href="{{ page.url }}">{{ page.title }}</a></li>
+    {% endfor %}
+  </ul>
+  <div>
+    <a href="{{ url_for('guides.guides_index') }}">&larr; All guide categories</a>
+  </div>
+</div>
+{% endblock %}