pgsql: Change format of SQL/MED generic options in psql backslash comma

Change format of SQL/MED generic options in psql backslash commands.

Rather than dumping out the raw array as PostgreSQL represents it
internally, we now print it out in a format similar to the one in
which the user input it, which seems a lot more user friendly.

Shigeru Hanada

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/0371d4d0632221957a60d4cdb70a898caf7ce6cf

Modified Files
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src/bin/psql/describe.c                    |   39 +++-
src/test/regress/expected/foreign_data.out |  345 ++++++++++++++--------------
src/test/regress/sql/foreign_data.sql      |   10 +-
3 files changed, 210 insertions(+), 184 deletions(-)