JS docs: add Options, Methods, Events subsections to nav sidebar

docs/_includes/js/tabs.html

@@ -91,7 +91,7 @@ $('#myTab li:eq(2) a').tab('show') // Select third tab (0-indexed)
 </div>
 {% endhighlight %}
 
-  <h3>Methods</h3>
+  <h3 id="tabs-methods">Methods</h3>
   <h4>$().tab</h4>
   <p>
     Activates a tab element and content container. Tab should have either a <code>data-target</code> or an <code>href</code> targeting a container node in the DOM.
@@ -118,7 +118,7 @@ $('#myTab li:eq(2) a').tab('show') // Select third tab (0-indexed)
 </script>
 {% endhighlight %}
 
-  <h3>Events</h3>
+  <h3 id="tabs-events">Events</h3>
   <p>When showing a new tab, the events fire in the following order:</p>
   <ol>
     <li><code>hide.bs.tab</code> (on the current active tab)</li>