Add webassets project

Webassets enables SCSS compilation and asset minification
The pelican-assets plugin was added to integrate it into Pelican
diff --git a/templates/article.html b/templates/article.html
index 0a7c43b..7940c11 100644
--- a/templates/article.html
+++ b/templates/article.html
@@ -8,7 +8,9 @@
   {{article.tags|join(', ') }}">
 
   {% if FUZZY_DATES %}
-  <script src="{{ SITEURL }}/theme/js/lw-timeago/lw-timeago.js" type="text/javascript"></script>
+  {% assets filters="slimit", output="js/lw-timeago.min.js", "js/lw-timeago/lw-timeago.js" %}
+  <script src="{{ SITEURL }}/{{ ASSET_URL }}" type="text/javascript"></script>
+  {% endassets%}
   {% endif %}
 {% endblock %}