[hibernate-dev] 6.0 - Type redesign

[Jordan Gigov]

While this topic is hot and the type handlers will not be
backwards-compatible, I think they should have some access to the
connection-specific Dialect. I have started (but largely paused) an
implementation of Array datatypes, but it's highly dependent on instance
type-checking of WrapperOptions ugly hackyness. It also needs to call
`java.sql.Connection.createArrayOf` on that same connection. Those two
interfaces should somehow be exposed to the type handlers at some point.
Also I haven't figured out yet how to use them as arrays of entity keys.
Storing an array of entities by their Id keys would be a nice bonus.