pgsql: Add comment that attributes.is_nullable was removed from SQL sta

Add comment that attributes.is_nullable was removed from SQL standard

We don't have to remove the column if no one is bothered, but it's
useful to comment on it in case someone looks for it in newer
standards versions.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/efb224a4392326fd6ae3eabdc170a246978d3f09

Modified Files
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src/backend/catalog/information_schema.sql |    2 +-
1 files changed, 1 insertions(+), 1 deletions(-)