"Nil" conflicts with the objective c macro of the same name.

On OSX, If you create a new project with Tinderbox and select the OSC block you will get a compile error about expanding the Nil macro.  I'm guessing with the app rewrite/dev changes, an objective c header is getting included now.  

I'm going to arbitrarily say that not many people are using the Nil structure with the stream operators, so this is likely a safe change. ;)