[cxx0x] stl_pair update patch

[Paolo Carlini]

Chris Fairles wrote:

>Wrote up a patch implementing 20.2.3 from N2369. Few questions:
>
>In the 'bits' headers, should I be using the __GXX_EXPERIMENTAL_CXX0X__
>macro to add cxx0x-only functionality? 
>
>I get circular-dependancy nightmares if I try to #include <utility> from
>within a "bits" header included from utility itself. Is the way I'm fwd
>declaring the type traits and identity/move/forward a satisfactory solution?
>  
>
Not really, but don't worry, as soon as the Copyright assignment is in 
place and we all agree about the substance of your patches, we can work 
out such simply details together.

Thanks,
Paolo.