Binary resultset patch v6

Hi,

I put a new version of the binary result set receiving patch here:
http://mokki.dyndns.org/~mtiihone/postgresql/binarytransfer/

Changes between v5 and v6 patch

- added infinite time/date/timestamp handling
- renames the binaryEncoding option to binaryTransfer
- disables binary transfers for updateable result sets
- cleans up all ResultSet get methods by forcing them to set the wasNullFlag
  in the checkResultSet method
- added binaryTransfer parameter to DataSource implementation

I think that the patch starts to be in a reasonable good shape for inclusion
into the 8.3dev driver. After inclusion I plan to start implementing the
sending of binary data to the backend.

-Mikko