Bigger change to NSView

[Fred Kiefer]

Some days ago I hacked in some new Cocoa methods to NSView (e.g. 
isHidden). To fully support the functionality here, we need another ivar 
to store the value for this. As you know, this change will require, to 
recompile all libraries and applications using local subclasses of 
NSView. Which will result in almost everything needing a recompile.

As this is a big step, I don't want to do it for the upcoming release, 
but rather for the 0.9.3 release. Given that backward compatibility gets 
broken anyway, we could think about making a few deeper changes in other 
places as well. For NSView we could merge all the boolean ivars into a 
bit structure, I don't think that this is really needed, still if we 
want to do it, we should do it now. Another place high up in the class 
hierarchy that springs to my mind as needing a few more ivars is NSCell. 
It would be great, if we could do as much of such deep changes in one 
go, to save the trouble of recompilations for all the other releases.

Fred