Update tooling (#99)

- Update browserify, serve, and tape to the latest versions
- update the example script to reflect serve's new CLI options
- Remove the uneeded dependency on opn-cli
- Force Travis to use NPM 5.x
- Remove bower.json

example/index.html

@@ -11,7 +11,7 @@
       <h1>Index</h1>
       Hello.
       Go to <a href='page2.html' class="js-Pjax">Page 2</a> and view your console to see Pjax events.
-      Clicking on <a href='index.html'>this page</a> will just reload the page entierly.
+      Clicking on <a href='index.html'>this page</a> will just reload the page entirely.
     </div>
   </body>
 </html>