mikeash/MAKVONotificationCenter — pull request #10 by TuongNM (2012-04-25 07:03:55+00:00)
Title: Made it work for iOS < 5.0 and Mac OS X < 10.7

I made this work for iOS < 5.0 and Mac OS X < 10.7 by checking for the Deployment target. If it's set to something before iOS 5.0 or Mac OS X 10.7, then ```NSOrderedSet``` won't be used and ```-deregister``` will use the ```-removeObserver:``` methods without the context parameter.
With these changes I was able to run this on a project targeted for iOS 4.3 and so far it seems to be working without problems.