pgsql: Add --no-blobs option to pg_dump

Add --no-blobs option to pg_dump

Add an option to exclude blobs when running pg_dump.  By default, blobs
are included but this option can be used to exclude them while keeping
the rest of the dump.

Commment updates and regression tests from me.

Author: Guillaume Lelarge
Reviewed-by: Amul Sul
Discussion: https://postgr.es/m/VisenaEmail.48.49926ea6f91dceb6.15355a48249@tc7-visena

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/4fafa579b0ab411f4cd2f30c57205d9b0ac27340

Modified Files
--------------
doc/src/sgml/ref/pg_dump.sgml    | 16 ++++++++
src/bin/pg_dump/pg_backup.h      |  1 +
src/bin/pg_dump/pg_dump.c        | 19 +++++++--
src/bin/pg_dump/t/002_pg_dump.pl | 86 +++++++++++++++++++++++++++++++++++++++-
4 files changed, 117 insertions(+), 5 deletions(-)