pgsql: Change hot_standby default value to 'on'

Change hot_standby default value to 'on'

This goes together with the changes made to enable replication on the
sending side by default (wal_level, max_wal_senders etc) by making the
receiving stadby node also enable it by default.

Huong Dangminh

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/34fc61673829f0cb63811fb63cc3c510fc2aadfc

Modified Files
--------------
doc/src/sgml/config.sgml | 2 +-
doc/src/sgml/high-availability.sgml | 4 ++--
src/backend/utils/misc/guc.c | 2 +-
src/backend/utils/misc/postgresql.conf.sample | 2 +-
4 files changed, 5 insertions(+), 5 deletions(-)