pgsql: Suppress foreign data wrappers and foreign servers in partial du

Suppress foreign data wrappers and foreign servers in partial dumps

This is consistent with the behavior of other global objects such as
languages and extensions.

Omitting foreign servers also omits the respective user mappings.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/3001b76308e9189ff471c54b1823621e03dc1359

Modified Files
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src/bin/pg_dump/pg_dump.c |   10 +++++++++-
1 files changed, 9 insertions(+), 1 deletions(-)