pgsql: Fix corner case for binary upgrade: extension functions in pg_ca

Fix corner case for binary upgrade: extension functions in pg_catalog.

Normally, pg_dump summarily excludes functions in pg_catalog from
consideration. However, some extensions may create functions in pg_catalog
(adminpack already does that, and extensions for procedural languages will
likely do it too). In binary-upgrade mode, we have to dump such functions,
or the extension will be incomplete after upgrading. Per experimentation
with adminpack.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/89c29c033154b717b16db2ee3c87bdec4393b0d4

Modified Files
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src/bin/pg_dump/pg_dump.c | 47 ++++++++++++++++++++++++++++++++++++--------
1 files changed, 38 insertions(+), 9 deletions(-)