[WIP] DDC-2622 - SQLServer expects the `OVER` clause to only include columns from the `FROM` clause

[DDC-2622](http://www.doctrine-project.org/jira/browse/DDC-2622) - SQLServer expects the `OVER` clause to only include columns from the `FROM` clause

As of http://technet.microsoft.com/en-us/library/ms189461.aspx :

 > `order_by_expression:

 > > Specifies a column or expression on which to sort. order_by_expression can only refer to columns made available by the FROM clause. An integer cannot be specified to represent a column name or alias.

That basically means that table aliases used to fetch the selected columns should NOT be included in the `OVER` clause.

This PR is required for doctrine/doctrine2#789