Made _getPickData more generic by supporting ordening
As such, renamed it to _getData.
Also use a more robust way to represent the filter in case it
contains entities.
Patch by: Sverre Rabbelier
from query import *
from subqueries import *
from where import AND, OR
from datastructures import EmptyResultSet
__all__ = ['Query', 'AND', 'OR', 'EmptyResultSet']