nl_langinfo: CODESET on MS-Windows and more items from localeconv
* lib/langinfo.in.h (DECIMAL_POINT, THOUSANDS_SEP, GROUPING)
(CURRENCY_SYMBOL, INT_CURR_SYMBOL, MON_DECIMAL_POINT)
(MON_THOUSANDS_SEP, MON_GROUPING, POSITIVE_SIGN, NEGATIVE_SIGN)
(FRAC_DIGITS, INT_FRAC_DIGITS, P_CS_PRECEDES, N_CS_PRECEDES)
(P_SEP_BY_SPACE, N_SEP_BY_SPACE, P_SIGN_POSN, N_SIGN_POSN): Define.
* lib/nl_langinfo.c: Include <locale.h> and <string.h> early.
Include <stdio.h> if Microsoft Windows.
Include <time.h> if !REPLACE_NL_LANGINFO.
(ctype_codeset): New function, taken from rpl_nl_langinfo,
and with improvements for Microsoft Windows.
(rpl_nl_langinfo): Use it.
(nl_langinfo) [!REPLACE_NL_LANGINFO]: Likewise.
Compute the values of RADIXCHAR, THOUSEP, GROUPING, CRNCYSTR,
INT_CURR_SYMBOL, MON_DECIMAL_POINT, MON_THOUSANDS_SEP,
MON_GROUPING, POSITIVE_SIGN, NEGATIVE_SIGN, FRAC_DIGITS,
INT_FRAC_DIGITS, P_CS_PRECEDES, N_CS_PRECEDES, P_SEP_BY_SPACE,
N_SEP_BY_SPACE, P_SIGN_POSN, and N_SIGN_POSN from the
corresponding values returned by 'localeconv'. Compute the values
of AM_STR, PM_STR, DAY_n, ABDAY_n, MON_n, and ABMON_n by calling
'strftime' with a suitable struct tm value.