1. `FetchMode::STANDARD_OBJECT` and `FetchMode::CUSTOM_OBJECT` are no longer supported.
2. `FetchMode::COLUMN` with a non-zero index is no longer supported.
3. Incompatible change in the `Connection::fetchColumn()` signature where the 3rd argument is now `$types`, not `$columnIndex`.

Removed the `Dbal` prefix from the class names and moved them to the `Doctrine\Tests\DBAL` namespace.

The SQLite and Oracle platforms produces a `ROUND()`'ed or `TRUNC()`'ated difference between the datetimes. However it should be the difference between dates.

statements in a rewindable iterator. Skipped the test for iterating
multiple times with a message regarding that iterators are non
rewindable.

Only added to mysqli for now, can add to other drivers (assuming they
support reseting the pointer in some way) after feedback.

Test fails because it's not possible to reuse a generator in this way.