title: javascript_include_tag 'application' not working
body: <p>In my <code>application.html.haml</code> I have <code>= javascript_include_tag 'application', 'data-turbolinks-track' =&gt; true</code></p>
  
  <p>Which is throwing the error: <code>TypeError: Object doesn't support this property or method
  (in C:/Ruby193/lib/ruby/gems/1.9.1/gems/turbolinks-2.5.1/lib/assets/javascripts/turbolinks.js.coffee)</code></p>
  
  <p>My <code>app/assets/javascripts/application.js</code> is:</p>
  
  <pre><code>//= require jquery
  //= require jquery_ujs
  //= require turbolinks
  //= require jquery.tablesorter
  //= require_tree .
  </code></pre>
  
  <p>and my gemfile includes:</p>
  
  <pre><code>gem 'jquery-rails'
  gem 'turbolinks'
  </code></pre>
  
  <p>Can anyone tell me what's going wrong? Thanks.</p>