pgsql: Avoid excessive Hot Standby feedback messages.

Avoid excessive Hot Standby feedback messages.

Without this patch, when wal_receiver_status_interval=0, indicating that no
status messages should be sent, Hot Standby feedback messages are instead sent
extremely frequently.

Fujii Masao, with documentation changes by me.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/59d6a7594288ebc909a24f3fc9e502f097bbe2ff

Modified Files
--------------
doc/src/sgml/config.sgml              |    7 ++++---
src/backend/replication/walreceiver.c |    2 +-
2 files changed, 5 insertions(+), 4 deletions(-)