Use a weak dependency to the JTS jar file (allow to use H2 without the JTS jar file in the classpath)

Use a weak dependency to the JTS jar file (allow to use H2 without the JTS jar file in the classpath)

Save some memory. There is no need to store a dataType field in the AggregateData structure when we can just pass it down. 

make some field names in Aggregate more obvious, to distinguish the special case GROUP_CONCAT fields from the normal fields

The purpose of this is to simplify the code for the individual cases to make it easier to implement analytic (windowing) functions.

for the "duplicate key exception" test, make it a little more flexible, because the format of the VALUES clause varies a little depending on the type of the index.

Issue 482: class LobStorageBackend$LobInputStream does not override method int avalaible() from InputStream

Add sufficient ClientInfo support to our javax.sql.Connection implementation to make WebSphere happy.