title: never ending Windows phone 8 background agent
body: <p>i Know how to create a background agent and how it invokes its onInvoke method.</p>
  
  <p>now is there any way i can create a background thread in the onInvoke method and do a long running task for 1-2 day?</p>
  
  <p>Please the question is not why would i need this,the question is weather it can be done or not.</p>
  
  <p>i don't want the agent to be scheduled for every 30 min,rather on its first invoke,it should start a background thread and do work unless its stopped by app logic.</p>
  
  <p>Thanks</p>