Add support for Java 8 Date and Time API AKA JSR-310. On the face of it
the existing JDBC types java.sql.Date, java.sql.Time and
java.sql.Timestamp offer conversion methods to and from JSR-310 data
types. Unfortunately java.sql.Timestamp does silent data truncation
when the timestamp falls into a DST transition on the JVM time zone.
Worse still for java.time.OffsetDateTime there is no corresponding JDBC
type. Therefore these conversions have to be implemented. All of this
has to be programmed using reflection so the code compiles and can be
executed on Java 7.

Fix bug in picking the right index for INSERT..ON DUPLICATE KEY UPDATE when there are both UNIQUE and PRIMARY KEY constraints.

Remove TO_DATE support from roadmap: It's already implemented

It's already implemented and working:
https://github.com/h2database/h2database/pull/150

Remove Java 6 backwards compatibility

Since we now require at least Java 6 we can remove the Java 6 backwards
compatibility layer.

Support byte[] in getObject

Add guards to JDBC debug code

The current implementation of getObject does not support byte[]. This
is an issue for some people [1].

 [1] https://groups.google.com/forum/#!topic/h2-database/InWprFw2B0o

Some of the existing JDBC code is missing guards around debug
statements that allocate strings.

Also build Java 8

To verify compatibility and for potential JSR-310 support
it would be good if we test against Java 8 as well.