pgsql: Fix some bogosities in pg_dump's foreign-table support.

Fix some bogosities in pg_dump's foreign-table support.

The server name for a foreign table was not quoted at need, as per report
from Ronan Dunklau. Also, queries related to FDW options were inadequately
schema-qualified in places where the search path isn't just pg_catalog, and
were inconsistently formatted everywhere, and we didn't always check that
we got the expected number of rows from them.

Branch
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REL9_1_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/5c19c057dcdaef08b89e751f7e335cc1f6a1e21f

Modified Files
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src/bin/pg_dump/pg_dump.c | 61 ++++++++++++++++++++++++++++----------------
1 files changed, 39 insertions(+), 22 deletions(-)