pgsql: Add: > * Allow libpq to access SQLSTATE so pg_ctl can test for

Log Message:
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Add:

* Allow libpq to access SQLSTATE so pg_ctl can test for connection failure

This would be used for checking if the server is up.

Modified Files:
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pgsql/doc:
TODO (r1.1363 -> r1.1364)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/TODO.diff?r1=1.1363&r2=1.1364)