[plugins] Convert to Markdown, normalize section names and URLs

_layouts/feature.html

@@ -15,9 +15,9 @@ title: Kernel & Plugins - Frama-C
         <div class="wrap">
 		  {% for tab in site.data.tabs %}
 			<a class="tabLink {% if page.active==forloop.index %}active locked{% endif %}" href="{{ tab.link }}">{{ tab.name }}</a>
-                     {% if not forloop.last %}
+                     {% unless forloop.last %}
                          <em></em>
-                     {% endif %}
+                     {% endunless %}
                 {% endfor %} 
 		
 		{% if page.active == 1 %}