Fix add_post encoding bug + some minor bugs

templates/generate.html

@@ -24,7 +24,7 @@
 {% else %}
 <table>
 {% for post in posts %}
-    <tr><td><a href="/post/edit/{{ post.id }}">{{ post.id }}</a></td><td>{{ post.title }}</td><td>{{ post.category.name }}</td><td>{{ post.creation_date }}</td><td>{{ post.published }}</td><td>{{ post.front_page }}</td><td><a href="/post/delete/{{ post.id }}">Delete</a></td></tr>
+    <tr><td><a href="/post/edit/{{ post.id }}">{{ post.id }}</a></td><td>{{ post.title }}</td><td>{{ post.category.name }}</td><td>{{ post.creation_date }}</td><td>{{ post.modification_date }}</td><td>{{ post.published }}</td><td>{{ post.front_page }}</td><td><a href="/post/delete/{{ post.id }}">Delete</a></td></tr>
 {% endfor %}
 {% endif %}
 </table>