     /**
 
      The singleton for Zephyr.
-     
+
      */
     private static let sharedInstance = Zephyr()
 
     /**
-    
+
      A shared key that stores the last synchronization date between NSUserDefaults and NSUbiquitousKeyValueStore
 
      */


    /**

     A debug flag. 
     
     If **true**, then this will enable console  log statements.

     By default, this flag is set to **false**.

    /**

     Zephyr's main synchronization method.

     Zephyr will synchronize all NSUserDefaults with NSUbiquitousKeyValueStore, depdending on what data is newer.

     If one or more keys are passed, only those keys will be synchronized.

     - parameter keys: If you pass a one or more keys, only those key will be synchronized. If no keys are passed, than all NSUserDefaults will be synchronized with NSUbiquitousKeyValueStore.
