title: I'd like to get a list of the top posts of all time in a subreddit using praw
body: <p>I can get the top posts for a certain day using the code below. Is there any way I can change this to the top posts of all time instead?</p>
  
  <pre><code>import praw
  
  user_agent = "Comment Reader 1.0 by /u/crowbell"
  
  r = praw.Reddit(user_agent=user_agent)
  
  submissions = r.get_subreddit('askreddit').get_top(limit=5)
  for x in submissions:
      print str(x)
  </code></pre>