[PATCH] libstdc++: implement locale support for AIX

[CHIGOT, CLEMENT]

> >Hi everyone, 
> >
> >I've reworked the patch to merged dragonfly and AIX
> >models into the new one named "ieee_1003.1-2008". 
> >It seems okay on the AIX part but if someone can test
> >on Dragonfly and Freebsd I would be glad. Configure
> >needs to be regenerated, first.
> 
> Presumably it could also be tested on GNU/Linux and Solaris, since
> they implement the POSIX 2008 APIs needed.
Indeed, I'll try it tomorrow for Linux. I don't have any Solaris 
VMs on my labs. 
Note that I've forgotten to add some "defined(__FreeBSD__)"
in the current patch, so it should not work on it. I'll send 
a better one tomorrow after having check on Linux.