Convert jdbcapi/XATest.java to junit
Client PreparedStatement in a global xact does not downgrade ResultSetHoldability to CLOSE_CURSORS_AT_COMMIT
committed converted test and removed redundant tests xaSimplePositive, xaMorph and xaStateTran
patch to convert XATest.java to Junit. I kept the same name, so XATest.java should be considered a new file, the diffs are not meaningful.