Add unavailable attribute and a warning for using NetworkActivityIndicatorManager on OS X.

Author: nlutsenko

Parse/PFNetworkActivityIndicatorManager.h

@@ -12,6 +12,7 @@
 
 #import <Parse/PFConstants.h>
 
+PF_OSX_UNAVAILABLE_WARNING
 PF_TV_UNAVAILABLE_WARNING
 PF_WATCH_UNAVAILABLE_WARNING
 
@@ -25,7 +26,7 @@ NS_ASSUME_NONNULL_BEGIN
  The number of active requests is incremented or decremented like a stack or a semaphore,
  the activity indicator will animate, as long as the number is greater than zero.
  */
-PF_TV_UNAVAILABLE PF_WATCH_UNAVAILABLE @interface PFNetworkActivityIndicatorManager : NSObject
+PF_OSX_UNAVAILABLE PF_TV_UNAVAILABLE PF_WATCH_UNAVAILABLE @interface PFNetworkActivityIndicatorManager : NSObject
 
 /**
  A Boolean value indicating whether the manager is enabled.