Trunk instability due to #215

[Lukas Eder]

Hi guys,

If anyone is planning on implementing things right now, expect some instabilities and some failing integration tests, as I am finally tackling the problems we had experienced eariler regarding null values in DB2 and now Derby. The problems will be resolved by introducing cast support (which is a nice-to-have feature anyway). I'll give up trying to find magic solutions for constant values and null literals that need explicit casting in some SQL dialects (DB2, Derby, HSQLDB), as the various use cases are too complex to find a general solution. As of version 1.5.4, I'll leave that responsibility to the client code. Clients can explicitly cast fields and constant values to any type.

This is the cast support ticket:
https://sourceforge.net/apps/trac/jooq/ticket/215

This change introduces (and also reveals) quite a few design problems that need fixing before the release of version 1.5.4. If you encounter any problems, please discuss them on this thread or contact me directly.

@Espen: First tests suggest, that cast support will allow for finally providing a stable fix for https://sourceforge.net/apps/trac/jooq/ticket/172

Cheers
Lukas