pgsql: Implement information_schema.parameters.parameter_default column

Implement information_schema.parameters.parameter_default column

Reviewed-by: Ali Dar <ali.munir.dar@gmail.com>
Reviewed-by: Amit Khandekar <amit.khandekar@enterprisedb.com>
Reviewed-by: Rodolfo Campero <rodolfo.campero@anachronics.com>

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/85ed91ee7da8f560c3443733cbda2862cd25facd

Modified Files
--------------
doc/src/sgml/information_schema.sgml            |    9 +++
src/backend/catalog/information_schema.sql      |    9 ++-
src/backend/utils/adt/ruleutils.c               |   84 +++++++++++++++++++++++
src/include/catalog/catversion.h                |    2 +-
src/include/catalog/pg_proc.h                   |    2 +
src/include/utils/builtins.h                    |    1 +
src/test/regress/expected/create_function_3.out |   33 ++++++++-
src/test/regress/sql/create_function_3.sql      |   24 +++++++
8 files changed, 160 insertions(+), 4 deletions(-)