Remove icon from GitHub link

Author: Sunderlandkyl

_includes/themes/twitter/top.html

@@ -42,7 +42,7 @@ <h2>Contact</h2>
   <div class="span4">
     <h2>GitHub</h2>
     <p>See the source code on GitHub.</p>
-    <p><a class="btn" href="https://github.com/PlusToolkit/PlusLib"><i class="images/GitHub-Mark-Light-32px.png"></i>View source code &raquo;</a></p>
+    <p><a class="btn" href="https://github.com/PlusToolkit/PlusLib">View source code &raquo;</a></p>
   </div>
 </div>