Mark test_range_necessary_list_calls() as xfail on Py2.6
Mark test_range_necessary_list_calls() as xfail on Py2.6

krischer/python-future,PythonCharmers/python-future,QuLogic/python-future,michaelpacer/python-future,michaelpacer/python-future,QuLogic/python-future,PythonCharmers/python-future,krischer/python-future