title: Redirect to log in page if user is not authenticated with Devise
body: <p>I'm using Devise with Ruby on Rails.</p>
  
  <p>What is the recommended way to redirect unauthenticated users to the sessions#new page if they attempt to access a page that requires authentication?</p>
  
  <p>Right now I get an error that says no route matches the one they attempt to access (leading to a 404 error in production).</p>