Oracle does not support any brackets around table name

I want to use Dibi PDO driver for communication with oracle database.

I have used following code
```php
$config = array(
	'dsn' => 'oci:dbname=//server.domain:1521/database',
	'username' => 'username',
	'password' => 'password',
);
$pdo = new PDO($config['dsn'], $config['username'], $config['password']);
$pdo->setAttribute(PDO::ATTR_CASE, PDO::CASE_LOWER);

$db_config = array(
	'driver' => 'pdo',
	'resource' => $pdo,
	'lazy' => TRUE,
);

$connection = new DibiConnection($db_config);
$query = $connection->select('*')->from('table')->where('column = %s', 'value');
var_dump($query->fetch());
```
But this failed with exception "OCIStmtExecute: ORA-00903: invalid table name", but table with this name really exists.

Output of plain sql contain bug:
```php
echo $query->__toString();
```
Result:
```sql
SELECT * FROM ( SELECT * FROM [table] WHERE column = 'value') WHERE ROWNUM <= 1
```

Oracle does not support square brackets around table name.
Expected query is:
```sql
SELECT * FROM ( SELECT * FROM table WHERE column = 'value') WHERE ROWNUM <= 1
```