Use relative base in footer url for image

Author: mcoonen

_includes/footer.html

@@ -5,7 +5,7 @@
     <div class="footer-wrapper">
         <div class="logo-symbol">
             <a class="logo-link" title="{{ site.title }}" href="{{ relativebase }}">
-                <img class="logo" id="logo" src="{{ site.logo-icon }}" alt="{{ site.title }}">
+                <img class="logo" id="logo" src="{{ relativebase }}{{ site.logo-icon }}" alt="{{ site.title }}">
             </a>
         </div>
         <div class="copyright">