pgsql: Make OFF keyword unreserved. It's not hard to imagine wanting to

Make OFF keyword unreserved. It's not hard to imagine wanting to use 'off'
as a variable or column name, and it's not reserved in recent versions of
the SQL spec either. This became particularly annoying in 9.0, before that
PL/pgSQL replaced variable names in queries with parameter markers, so
it was possible to use OFF and many other backend parser keywords as
variable names. Because of that, backpatch to 9.0.

Branch
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REL9_0_STABLE

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=143b8cbceec0d15dd5c747e2c45a4b0a762af6f0

Modified Files
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src/backend/parser/gram.y | 26 +++++++++++++-------------
src/include/parser/kwlist.h | 2 +-
2 files changed, 14 insertions(+), 14 deletions(-)