title: Kill all instances of an Activity
body: <p>I'm setting up Notifications in my app and I've noticed whilst testing, after clicking a new notifications (in this case the notification loads a blog details page), I have many instances of the blog details activity running (pressing back it shows each activity with the previously loaded blogs).</p>
  
  <p>Is it possible in my Receiver class, so look if there is any instance of <code>ActivityBlog</code> already running, and if there all <code>.finish()</code> them all so there is only ever once instance running?</p>
  
  <p>I found <a href="https://stackoverflow.com/questions/14766929/finish-all-instance-of-particular-activity">this</a> but I couldn't work out a way to do it from that.</p>