Return list of matching records. criteria is a dict of {field: value}

        >>> s = teststore()
        >>> s.list('tstoretest')
        []

def list(self, cls, criteria=None):
        """
        Return list of matching records. criteria is a dict of {field: value}

        >>> s = teststore()
        >>> s.list('tstoretest')
        []
        """
        self.validate_criteria(cls, criteria)
        return self.db.select(cls, where=criteria)