Support for Oracle Wallet JDBC connections

In the latest snapshot build, Narayana will replace a null username and/or password with empty strings (""). The Oracle JDBC driver, however, supports passing in null username and password, in order to make use of Oracle Wallet.

This means that Narayana does not support Oracle Wallet JDBC connections.

This replacement is being done in com.arjuna.ats.internal.jdbc.ConnectionImple.

            user = info.getProperty(TransactionalDriver.userName, "");
            passwd = info.getProperty(TransactionalDriver.password, "");

and in com.arjuna.ats.internal.jdbc.ConnectionManager

        String user = info.getProperty(TransactionalDriver.userName, "");
        String passwd = info.getProperty(TransactionalDriver.password, "");

I believe it should be okay to just remove default value so that the client's input is always taken as-is?