ent/doc: add recursive o2o relation

Reviewed By: alexsn

Differential Revision: D17046402

fbshipit-source-id: 0796e289816aed9755af94be05c572efbe85d49d

doc/website/static/js/code-block-buttons.js

@@ -44,4 +44,9 @@ window.addEventListener('load', function() {
             textEl.textContent = 'Copy';
         }, 2000);
     });
+
+    // add an id tag for images based on their alt attribute.
+    document.querySelectorAll('.container img').forEach(function(el) {
+        el.id = el.alt;
+    });
 });