pgsql: Fix encoding issue when lc_monetary or lc_numeric are different

Log Message:
-----------
Fix encoding issue when lc_monetary or lc_numeric are different encoding
from lc_ctype, that could happen on Windows. We need to change lc_ctype
together with lc_monetary or lc_numeric, and convert strings in lconv
from lc_ctype encoding to the database encoding.

The bug reported by Mikko, original patch by Hiroshi Inoue,
with changes by Bruce and me.

Modified Files:
--------------
    pgsql/src/backend/utils/adt:
        pg_locale.c (r1.53 -> r1.54)
        (http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/pg_locale.c?r1=1.53&r2=1.54)