title: differentiate between single click and double click on Home button in iOS
body: <p>I want to handle single click and double click on Home button separately.
  I know <code>applicationWillResignActive:</code> but it gets call in both conditions.
  <code>applicationDidEnterBackground:</code> but I want to process data before app goes in background not after.</p>
  
  <p>Is there any way I can recognise <em>single</em> and <em>double</em> click on home button separately?</p>