* Use a non-UTC timezone when testing the PostgreSQL timezone support.
* Fix serialization of time of day values for PostgreSQL
* Fix serialization of PostgreSQL values for "timestamp with time zone" and "time with time zone" fields.
* When inserting values into "timestamp with time zone" fields treat the value as being in the UTC time zone.
* Simplify parsing of PostgreSQL date/time responses by using regular expressions. Always convert response times with time zone to UTC.
* Add tests which check if timestamp and date fields are treated as having a UTC time zone.
* Clarify the test comments.
