pgsql: Add: > * Allow a warm standby system to also allow read-only

Log Message:
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Add:

* Allow a warm standby system to also allow read-only queries

This is useful for checking PITR recovery.

Modified Files:
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pgsql/doc:
TODO (r1.1414 -> r1.1415)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/TODO.diff?r1=1.1414&r2=1.1415)