Apple binar property lost format

[Fred Kiefer]

I did just commit the writing of property lists in the Apple binary 
format. This should make it easier to write NIB files that may be used 
on Apple systems. But of course we will need full keyed encoding first.

There are two known limitations to this implementation. First NSNumber 
objects containing char values with 0 or 1 are treated as NO and YES. 
This wont make much of a difference for the applications reading this 
data, but is not strictly correct. I could not find any way to handle 
this better, apart from checking for an internal class name. After all 
this is still a lot better than the XML output format code, which treats 
all char numbers as boolean.

The other limitation is that when reading in a binary property list and 
storing it again in the same format, the number of objects decreses. I 
am not sure what is causing this, it also only happens with big NIB 
files. My only idea is that my code in [BinaryPLGenerator 
indexForObject:] removes duplicate occurences of objects. Maybe Apple 
stores them each anew. If somebody can confirm this, I would adjust my 
code. But then the code would no longer be able to handle recursive 
property list.

Cheers
Fred