[autoscaler] Fix confirmation (y/N) for autoscaler for Python 2 (#1450)
[autoscaler] Fix confirmation (y/N) for autoscaler for Python 2 (#1450)

* Fix autoscaler for Python 2

* fix version test

* add linting exception for raw_input in Python 3

* two spaces

stephanie-wang/ray,richardliaw/ray,richardliaw/ray,richardliaw/ray,atumanov/ray,stephanie-wang/ray,atumanov/ray,ray-project/ray,robertnishihara/ray,pcmoritz/ray-1,ujvl/ray-ng,pcmoritz/ray-1,pcmoritz/ray-1,robertnishihara/ray,atumanov/ray,richardliaw/ray,ray-project/ray,ray-project/ray,stephanie-wang/ray,ray-project/ray,ray-project/ray,ray-project/ray,pcmoritz/ray-1,robertnishihara/ray,robertnishihara/ray,atumanov/ray,stephanie-wang/ray,richardliaw/ray,atumanov/ray,atumanov/ray,robertnishihara/ray,ujvl/ray-ng,atumanov/ray,richardliaw/ray,robertnishihara/ray,richardliaw/ray,stephanie-wang/ray,richardliaw/ray,pcmoritz/ray-1,ujvl/ray-ng,robertnishihara/ray,stephanie-wang/ray,atumanov/ray,stephanie-wang/ray,ray-project/ray,ujvl/ray-ng,ray-project/ray,pcmoritz/ray-1,pcmoritz/ray-1,pcmoritz/ray-1,robertnishihara/ray,robertnishihara/ray,stephanie-wang/ray,stephanie-wang/ray