Quick-Search: Added Quick-search in the topbar

Changed how and what we store in elastic to unify it with how we store
things in mongodb so we can have more generic javascript code
to render the data.

Elastic changes:
  Added:
  Node.project.url

  Altered to store id instead of url
  Node.picture

  Made Post searchable

./manage.py elastic reset_index
./manage.py elastic reindex

Thanks to Pablo and Sybren

src/templates/production.pug

@@ -9,7 +9,7 @@ mixin group(title, tag)
 
 			h4.title-underline.mt-2.mb-4
 				a.text-muted(href="#" + tag)= title
-			+card-deck(data-asset-tag=tag, class="js-asset-list py-3")
+			+card-deck(data-asset-tag=tag, class="js-asset-list p-3")
 
 | {% block page_title %}Production Lessons{% endblock %}
 | {% set page_header_text = "Tips and tricks by the Open Projects crew." %}