title: Rails 3 public_activity, destroy record
body: <p>I am using the <a href="https://github.com/pokonski/public_activity" rel="nofollow">public_activity</a> gem tracking if a user creates a post.
  Is there a way to destroy a public activity record, on deletion of the post, so that in the activities feed it doesn't show something like:</p>
  
  <pre><code>A post was deleted.
  </code></pre>
  
  <p>And instead just deletes that particular activity in the activities table </p>
  
  <p>Thanks.</p>