pgsql: Add description: < information, either by name or offset from

Log Message:
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Add description:

< information, either by name or offset from UTC

information, either zone name or offset from UTC

If the TIMESTAMP value is stored with a time zone name, interval
computations should adjust based on the time zone rules, e.g. adding
24 hours to a timestamp would yield a different result from adding one
day.

Modified Files:
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pgsql/doc:
TODO (r1.1400 -> r1.1401)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/TODO.diff?r1=1.1400&amp;r2=1.1401)