title: How to pause execution using guard and pry?
body: <p>I have Rails 3.1.1 app with this guardfile:</p>
  
  <pre><code>guard 'bundler' do
    watch('Gemfile')
  end
  
  guard 'rails' do
    watch('Gemfile.lock')
    watch(%r{^(config|lib)/.*})
  end
  </code></pre>
  
  <p>When my app is running under guard, a call to <code>binding.pry</code> does not pause execution. How do I make that happen?</p>