Add URLs to document why DLLIMPORT is needed on Windows.

Per email from Craig Ringer

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/aa69670e4296321b51251d34e9bd2c4bc17aab75

Modified Files
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src/include/port/win32.h |    8 +++++++-
1 files changed, 7 insertions(+), 1 deletions(-)

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	Subject: pgsql: Don't try to use a unopened relation