feat (Statement.php) add support for type and length in binding

Specifing binding in manner [value, length, type] will affect call of oci_bind_by_name.
Alternative syntax is ['value' => value, 'length' => length, 'type' => type]
If binding variable is not array default values of length and type are applied
feat (Db.php) add call() method to execute PL/SQL functions
feat (Statement.php) add item length and type options to bindArray() method