Add fade effect to tabs

ttlib/about/index.tt

@@ -12,7 +12,7 @@
                 <li><a href="#author" data-toggle="tab">Author</a></li>
               </ul>
               <div class="tab-content">
-                <div class="tab-pane active" id="site">
+                <div class="tab-pane active fade in" id="site">
                   <p>Since the last general election in 2010, Twitter use in the UK has
                     expanded massively. You're no-one if you're not on Twitter.</p>
                   <p>With that in mind, this site gives you a simple way to track what
@@ -24,7 +24,7 @@
                   <p>If you find this site useful, please
                     <a href="https://twitter.com/TwittElection">let us know</a>.</p>
                 </div>
-                <div class="tab-pane" id="tech">
+                <div class="tab-pane fade" id="tech">
                   <p>This site is built using the <a href="https://dev.twitter.com/rest/public">Twitter API</a>.</p>
                   <p>The site was built using
                     <a href="http://getbootstrap.com">Bootstrap</a>,
@@ -38,7 +38,7 @@
                     any information about candidates for the upcoming election, then please consider
                     sharing it there.</p>
                 </div>
-                <div class="tab-pane" id="author">
+                <div class="tab-pane fade" id="author">
                   <p><a href="http://dave.org.uk/">Dave Cross</a> was convinced that the 2010 general
                     election would be dominated by Twitter. He was wrong, but now thinks that if he
                     makes the same prediction for every general election he'll get it right eventually.</p>