Recover for "page store" H2   breaks LOBs consistency

Run tests on Travis

Run the tests on Travis so that when a pull request breaks some tests
we notice it immediately.

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.