Fix and improve docs on tab config

docs/javascript.html

@@ -638,6 +638,11 @@ $('#myModal').on('hidden', function () {
           <h2>Using bootstrap-tab.js</h2>
           <p>Enable tabbable tabs via javascript:</p>
           <pre class="prettyprint linenums">$('#myTab').tab('show')</pre>
+          <p>You can also activate a specific tab (or a pseudo-selected one) on init:</p>
+<pre class="prettyprint linenums">
+$('#myTab a[href="#profile"]').tab('show');
+$('#myTab a:last').tab('show');
+</pre>
           <h3>Markup</h3>
           <p>You can activate a tab or pill navigation without writing any javascript by simply specifying <code>data-toggle="tab"</code> or <code>data-toggle="pill"</code> on an element.</p>
 <pre class="prettyprint linenums">
@@ -653,7 +658,7 @@ $('#myModal').on('hidden', function () {
             Activates a tab element and content container. Tab should have either a `data-target` or an `href` targeting a container node in the dom.
           </p>
 <pre class="prettyprint linenums">
-&lt;ul class="nav nav-tabs"&gt;
+&lt;ul class="nav nav-tabs" id="myTab"&gt;
   &lt;li class="active"&gt;&lt;a href="#home"&gt;Home&lt;/a&gt;&lt;/li&gt;
   &lt;li&gt;&lt;a href="#profile"&gt;Profile&lt;/a&gt;&lt;/li&gt;
   &lt;li&gt;&lt;a href="#messages"&gt;Messages&lt;/a&gt;&lt;/li&gt;
@@ -669,7 +674,7 @@ $('#myModal').on('hidden', function () {
 
 &lt;script&gt;
   $(function () {
-    $('.tabs a:last').tab('show')
+    $('#myTab a:last').tab('show')
   })
 &lt;/script&gt;</pre>
           <h3>Events</h3>