Bump version number to 0.3.7

Convert Query to Expression<T> for usage as subquery

Query can now be converted to a typed expression to support use of subqueries.

Introduce SqlStatement to replace awkward usages of Expression when no type is needed
nor known.

Support NULLS LAST and NULLS FIRST options in ORDER BY clauses

Move specific operations to Select

Remove grouping, distinct and having from Query and make them specific to Select.
Other types of queries, such as unions, might not some of them.

Set version number to 0.3.3

Bump version number to 0.3.2

Accept any type of expression in ORDER BY clauses

Bump version number to 0.3.0

Use TIMESTAMP WITH TIMEZONE for Instant type columns

Change SQL type for Instant columns to TIMESTAMP WITH TIMEZONE
using the UTC timezone. This better fits the fact that a
timestamp is a point on the timeline. Some drivers (e.g. Postgres)
always store timestamps in UTC and getting the timestamp
in the client timezone (see JDBC spec) is confusing.

TIMESTAMP (WITHOUT TIMEZONE) is reserved for LocalDate.

Bump version number to 0.2.4