pgsql: Undo perl's nasty locale setting on Windows.

Log Message:
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Undo perl's nasty locale setting on Windows. Since we can't do that as
elsewhere by setting the environment appropriately, we make perl do it
right after interpreter startup by calling its POSIX::setlocale().

Tags:
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REL8_1_STABLE

Modified Files:
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pgsql/src/pl/plperl:
plperl.c (r1.94.2.4 -> r1.94.2.5)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/pl/plperl/plperl.c.diff?r1=1.94.2.4&r2=1.94.2.5)