title: Pass info from PreferenceActivity to ControlExtension SW2
body: <p>I'm trying to pass data from the <code>PreferenceActivity</code> to the <code>ControlExtension</code> and I don't really know how to do that. 
  I'm trying to use the <code>BroadcastReceiver</code> solution, because <code>SharedPreferences</code> doesn't work for my, but without knowing how yo use it so, ¿how and where I should register the <code>BroadcastReceiver</code> for the SW2?</p>
  
  <p>Thanks in advance</p>
  
  <p>EDIT:</p>
  
  <p>I'm using now <code>BroadcastReceiver</code> but I ¿How do I have register my <code>BroadcastReceiver</code> in the <code>ControlExtension</code>? or ¿How do I start my <code>ControlExtension</code> from the <code>ExtensionReceiver</code>?</p>