Update documentation

css/default.css

@@ -37,13 +37,6 @@ body.index-page #main-content iframe.github-star-button {
     margin-right: -15px;
 }
 
-/* Tweet button */
-body.index-page #main-content iframe.twitter-share-button {
-    float: right;
-    margin-top: -12px;
-    margin-right: 8px;
-}
-
 /* Travis CI and PyPI badge */
 body.index-page #main-content img.status-badge {
     float: right;

index.html

@@ -417,9 +417,6 @@
               <p class="badges" height=20px>
     <iframe src="http://ghbtns.com/github-btn.html?user=tomchristie&amp;repo=django-rest-framework&amp;type=watch&amp;count=true" class="github-star-button" allowtransparency="true" frameborder="0" scrolling="0" width="110px" height="20px"></iframe>
 
-    <a href="https://twitter.com/share" class="twitter-share-button" data-url="django-rest-framework.org" data-text="Checking out the totally awesome Django REST framework! http://www.django-rest-framework.org" data-count="none"></a>
-    <script>!function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="http://platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs");</script>
-
     <a href="http://travis-ci.org/tomchristie/django-rest-framework?branch=master">
         <img src="https://secure.travis-ci.org/tomchristie/django-rest-framework.svg?branch=master" class="status-badge">
     </a>