title: Upgrade to Rails 4 led to rspec output hanging
body: <p>I've upgraded to Rails 4.0.0 from Rails 3.2.13. I fixed all the deprecation warnings (except for secret_base_key), upgraded database_cleaner, rspec, rspec-rails, capybara, selenium-webdriver and poltergeist to the latest versions. </p>
  
  <p>Now, when I run my specs, through rake or rspec, the output of rspec eventually hangs, always on a feature test (a javascript one). The output of test.log is clear: the tests are still running, but the console is not getting any updates.</p>
  
  <p>I am using:</p>
  
  <ul>
  <li>phantomjs 1.9.2.</li>
  <li>poltergeist 1.4.1</li>
  </ul>
  
  <p>Thoughts on how I can get my test suite to behave normally again?</p>