pgsql-server: Add: > * Add session start time and last statement time

Log Message:
-----------
Add:

* Add session start time and last statement time to pg_stat_activity

Modified Files:
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pgsql-server/doc:
TODO (r1.1298 -> r1.1299)
(http://developer.postgresql.org/cvsweb.cgi/pgsql-server/doc/TODO.diff?r1=1.1298&r2=1.1299)