title: Go back to a specific activity without starting it again
body: <p>'suppose i have activities A,B,C,D.
  i start these activities like A->B->C->D
  now i want to go back to A on the click of a button without loading its 
  data again.
  note: i don't want this all on backpress. </p>
  
  <p>i have already tried.'</p>
  
  <pre><code>Intent intent = new Intent(getActivity(),
  A.class);
  intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
  startActivity(intent);
  </code></pre>
  
  <p>'but the reason is that it start the A again. all the api's calls again. </p>
  
  <p>what i want is that. for example i have two activities like 1,2
  and i start them like 1->2
  now if i finish 2 on a button click 1 will be shown to me without 
  starting it again. i want the same thing from D to A on the click of a 
  button not on back press.'</p>