pgsql: pg_waldump: Add a --quiet option.

pg_waldump: Add a --quiet option.

The primary motivation for this change is that it will be used by the
upcoming patch to add backup manifests, but it also seems to have some
potential more general use.

Andres Freund and Robert Haas

Discussion: http://postgr.es/m/20200330020814.nspra4mvby42yoa4@alap3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/ac44367efbef198c57a18b96dbc6a39191720994

Modified Files
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doc/src/sgml/ref/pg_waldump.sgml | 12 ++++++++++++
src/bin/pg_waldump/pg_waldump.c  | 22 ++++++++++++++++------
2 files changed, 28 insertions(+), 6 deletions(-)