update ShiftedPeriodicOperator.__init__() for pyflakes
update ShiftedPeriodicOperator.__init__() for pyflakes

lokik/sfepy,RexFuzzle/sfepy,BubuLK/sfepy,vlukes/sfepy,RexFuzzle/sfepy,RexFuzzle/sfepy,lokik/sfepy,vlukes/sfepy,RexFuzzle/sfepy,lokik/sfepy,rc/sfepy,lokik/sfepy,sfepy/sfepy,sfepy/sfepy,BubuLK/sfepy,rc/sfepy,BubuLK/sfepy,vlukes/sfepy,rc/sfepy,sfepy/sfepy