implies more memory copy. The old method is still available and can be used.
It stays as default. Choosing the method is through a flag to mysqli_query()/mysqli_real_query()
New mode can be forced with an INI setting, for all extensions that support this mode
(ext/mysql and mysqli, because PDO due to it's architecture can't support it)
The setting is mysqlnd.fetch_data_copy=[0|1]
methods for the handle and the data object.
Add auxiliary functions to work with the new methods.
Add possibility to clone a connection object - shadow copy.
