[v3] speedup numpunct cache a bit

[B. Kosnik]

>2003-06-27  Jerry Quinn  <jlquinn@optonline.net>
>
>	* src/locale.cc (__use_cache<numpunct>): Move from here ...
>	* include/bits/locale_facets.tcc (__use_cache<numpunct>): To
>	here.

Looks fine Jerry. 

Thanks!

-benjamin