Fix Image.save() and ImageSet.save() for Windows environment.
Fix Image.save() and ImageSet.save() for Windows environment.

Image.save() and ImageSet.save() use Image.save(temp=True) for
saving temporary files for notebook instead of generating paths of
them manually. The function had not worked well on Windows
environment because it had generated invalid (at least on Windows)
paths by simply adding '/tmp/' as a prefix.

sightmachine/SimpleCV2,jlegendary/SimpleCV,tpltnt/SimpleCV,gskielian/SimpleCV,jayrambhia/SimpleCV2,sightmachine/SimpleCV,sightmachine/SimpleCV,tpltnt/SimpleCV,beni55/SimpleCV,sightmachine/SimpleCV,tpltnt/SimpleCV,nils-werner/SimpleCV,hayd/SimpleCV,sightmachine/SimpleCV2,jlegendary/SimpleCV,jyt109/SimpleCV,hurdlea/SimpleCV,jlegendary/SimpleCV,nils-werner/SimpleCV,tpltnt/SimpleCV,jyt109/SimpleCV,gskielian/SimpleCV,sightmachine/SimpleCV2,jayrambhia/SimpleCV2,beni55/SimpleCV,nils-werner/SimpleCV,onaclovtech/SimpleCV,onaclovtech/SimpleCV,sightmachine/SimpleCV,sightmachine/SimpleCV2,jlegendary/SimpleCV,beni55/SimpleCV,gskielian/SimpleCV,tpltnt/SimpleCV,onaclovtech/SimpleCV,hurdlea/SimpleCV,sightmachine/SimpleCV,nils-werner/SimpleCV,onaclovtech/SimpleCV,nils-werner/SimpleCV,beni55/SimpleCV,hayd/SimpleCV,beni55/SimpleCV,gskielian/SimpleCV,hayd/SimpleCV,hurdlea/SimpleCV,hurdlea/SimpleCV,jyt109/SimpleCV,hurdlea/SimpleCV,gskielian/SimpleCV,jayrambhia/SimpleCV2,jayrambhia/SimpleCV2,jyt109/SimpleCV,hayd/SimpleCV,onaclovtech/SimpleCV,jyt109/SimpleCV,jlegendary/SimpleCV,hayd/SimpleCV