[ehn] Add possibility to add icon in results (more ugly html / css, need fix)

searx/templates/result_templates/default.html

 
   {% if result['favicon'] %}
   <div style="float:left; margin:2px;">
-    <img width="18" height="18" src="static/img/icon_{{result['favicon']}}.png" alt="{{result['favicon']}}.png" title="{{result['favicon']}}.png" />
+    <img width="18" height="18" src="static/img/icon_{{result['favicon']}}.ico" alt="{{result['favicon']}}.ico" title="{{result['favicon']}}.ico" />
   </div>
   {% endif %}