Explicit ad type

Author: davidfischer

docs/_templates/ethicalads.html

@@ -1,4 +1,4 @@
 <div id="rtd-stickybox">
   <div class="stickybox-hide" onclick="document.querySelector('#rtd-stickybox').remove();">&#215;</div>
-  <div class="raised" data-ea-publisher="readthedocs"></div>
+  <div class="raised" data-ea-publisher="readthedocs" data-ea-type="image"></div>
 </div>