pgsql: Change recovery.conf.sample to match postgresql.conf by showing

Log Message:
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Change recovery.conf.sample to match postgresql.conf by showing only
default values, with example comments.

Modified Files:
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pgsql/src/backend/access/transam:
recovery.conf.sample (r1.7 -> r1.8)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/access/transam/recovery.conf.sample?r1=1.7&r2=1.8)