pgsql: Update Windows timezone mapping from Windows 7 and 10

Update Windows timezone mapping from Windows 7 and 10

This adds a couple of new timezones that are present in the newer
versions of Windows. It also updates comments to reference UTC rather
than GMT, as this change has been made in Windows.

Michael Paquier

Branch
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REL9_5_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/a0833b972bd1e1198486bcea1651fcbd160a02c3

Modified Files
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src/bin/initdb/findtimezone.c | 389 ++++++++++++++++++++++++++++++------------
1 file changed, 281 insertions(+), 108 deletions(-)