Log Message:
py-python-sql: update to 0.9

Version 0.9:
* Add distinct_on on Select
* Allow to use Select as Column of Select query
* Support Select without from clause

Version 0.8:
* Add DISTINCT qualifier to aggregate expressions
* Allow to order on select queries
* Add NULL ordering
* Use UPPER to simulate missing ILIKE
* Add CURRENT_DATE function
* Fix DateTrunc function name
* Add no_boolean Flavor
* Add converter format2numeric
* Add rownum limit style
* Add no_as Flavor