Make tooltip-viewport example work.

[ci skip]

docs/examples/tooltip-viewport/index.html

@@ -7,7 +7,7 @@
     <!-- The above 3 meta tags *must* come first in the head; any other head content must come *after* these tags -->
     <meta name="description" content="">
     <meta name="author" content="">
-    <link rel="shortcut icon" href="../../assets/ico/favicon.ico">
+    <link rel="shortcut icon" href="../../favicon.ico">
 
     <title>Tooltip Viewport Example for Bootstrap</title>
 
@@ -42,6 +42,7 @@
     <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>
     <script>window.jQuery || document.write('<script src="../../assets/js/vendor/jquery.min.js"><\/script>')</script>
     <script src="../../dist/js/bootstrap.min.js"></script>
+    <script src="../../assets/js/vendor/tether.min.js"></script>
     <!-- IE10 viewport hack for Surface/desktop Windows 8 bug -->
     <script src="../../assets/js/ie10-viewport-bug-workaround.js"></script>
     <script src="tooltip-viewport.js"></script>