title: parse error for updating devicetoken in installation table
body: <p>I am trying to update <code>deviceToken</code> of <code>parse</code> <code>Installation</code>  table. i am using via <code>rest</code> api for android. but whenever i update my <code>devicetoken</code>  via following code</p>
  
  <pre><code>ParseInstallation installation = ParseInstallation.getCurrentInstallation();
  LinkedList&lt;String&gt; channels = new LinkedList&lt;String&gt;();     
  channels.add("Giants");    
  installation.put("channels",channels);     
  installation.put("GCMSenderId","56698194487");     
  installation.put("deviceToken","abcd");    
  installation.saveInBackground();   
  </code></pre>
  
  <p>I got following error      </p>
  
  <blockquote>
    <p>Caused by: java.lang.IllegalArgumentException: Cannot modify
    <code>deviceToken</code> property of an _Installation object.</p>
  </blockquote>
  
  <p>I tried to delete <code>session</code> and <code>installation</code> table but nothing works could anyone help me?</p>