title: didUpdateLocations always be called several times with different coordinates
body: <p>So, my app requires to capture location every 15 meter.</p>
  
  <p>in viewDidLoad</p>
  
  <pre><code>NSOperationQueue.mainQueue().addOperationWithBlock {
      self.manager = CLLocationManager()
      self.manager.delegate = self
      self.manager.desiredAccuracy = kCLLocationAccuracyNearestTenMeters
      self.manager.distanceFilter = 15.0
      self.manager.headingFilter = 10
      self.manager.startUpdatingLocation()
  }
  </code></pre>
  
  <p>First time (i don't move), in </p>
  
  <pre><code>func locationManager(manager:CLLocationManager, didUpdateLocations locations:[AnyObject])
  </code></pre>
  
  <p>i get (real example):
  *.1488241293991
  *.5997807433053</p>
  
  <p>second time:
  *.1489010891664
  *.599624152471</p>
  
  <p>I test on real device with ios7, and swift.</p>
  
  <p>What am I doing wrong?</p>
  
  <p>Thanks!</p>