UX + HTML corrections

Add title on image for hover
Add alt on favicon

searx/templates/oscar/result_templates/images.html

 <a href="{{ result.img_src }}" data-toggle="modal" data-target="#modal-{{ index }}">
-    <img src="{{ result.img_src }}" alt="{{ result.title|e }}" class="img-thumbnail">
+    <img src="{{ result.img_src }}" alt="{{ result.title|e }}" title="{{ result.title|e }}" class="img-thumbnail">
 </a>
 
 <div class="modal fade" id="modal-{{ index }}" tabindex="-1" role="dialog" aria-hidden="true">
         <div class="modal-content">
             <div class="modal-header">
                 <button type="button" class="close" data-dismiss="modal"><span aria-hidden="true">&times;</span><span class="sr-only">Close</span></button>
-                <h4 class="modal-title">{% if result['favicon'] %}<img width="32" height="32" class="favicon" src="static/{{ theme }}/img/icons/{{ result['favicon'] }}.png" /> {% endif %}{{ result.title|striptags }}</h4>
+                <h4 class="modal-title">{% if result['favicon'] %}<img width="32" height="32" class="favicon" src="static/{{ theme }}/img/icons/{{ result['favicon'] }}.png" alt="{{ result['favicon'] }}" /> {% endif %}{{ result.title|striptags }}</h4>
             </div>
             <div class="modal-body">
                 <img class="img-responsive center-block" src="{{ result.img_src }}" alt="{{ result.title }}">