XADataSource/ConnectionPoolDataSource code (experimental)

DatabaseMetaData.getPrimaryKeys() and getBestRowIdentifier() are now more robust in identifying primary keys (matches regardless of case or abbreviation/full spelling of Primary Key in Key_type column).

Batch updates now supported (thanks to some inspiration from Daniel Rall).

PreparedStatement.setAnyNumericType() now handles positive exponents correctly (adds + so MySQL can understand it).