[v3] add max_size and rebind to __alloc_traits

[Paolo Carlini]

Hi,
> I think you're right it wasn't failing before, as I ran the whole 
> testsuite in C++0x mode when I first added alloc_traits - I'll check 
> it today and see how I broke it. 
Thanks. In the meanwhile I checked r179522 and in fact yesterday I was 
wrong, it already failed (we had quite a bit of noise in the testsuite 
run in C++0x mode, I'm in the process of dealing with the most obvious 
issues, like pod_char_traits.h).

Now it remains to be assessed whether it's Ok for it to fail ;)

Paolo.