jdbc: Support Statement max field size

[nicktorwald]

Support following API get/set maxFieldSize

... the limit for the maximum number of bytes that can be returned for character and binary column values in a ResultSet object produced by this Statement object. This limit applies only to BINARY, VARBINARY, LONGVARBINARY, CHAR, VARCHAR, NCHAR, NVARCHAR, LONGNVARCHAR and LONGVARCHAR fields. If the limit is exceeded, the excess data is silently discarded. For maximum portability, use values greater than 256.

It may be done on the driver side. For example, ResultSet can trim string/bytes results internally.