Add insert_code_chunks template filter

This basic version actually removes them. Addition to be coming later

blog/templates/blog/post.html

@@ -1,10 +1,7 @@
 <div class="post">
     <h3>{% if title_links %}<a href="{% url 'blog:read' post.created_at.year post.created_at.month post.created_at.day post.slug %}">{% endif %}{{ post.title }}{% if title_links %}</a>{% else %}<div class="plusone-container"><div class="g-plusone" data-annotation="inline" data-size="small" data-width="300"></div></div>{% endif %}</h3>
     <p class="article-date">{{ post.created_at|date:'m-d-Y :: H:i' }} by {{ post.user.first_name }} {{ post.user.last_name }}</p>
-    {% comment %}
     {{ post.content|insert_code_chunks }}
-    {% endcomment %}
-    {{ post.content|safe }}
 {% if post.tags.all %}
     <p class="article-tags">Tags:
 {% for tag in post.tags.all %}