clarified transform_reduce() semantics
clarified transform_reduce() semantics

malenie/thrust,julianromera/thrust,google-code-export/thrust,UIKit0/thrust,bfurtaw/thrust,levendlee/thrust,Vishwa07/thrust,allendaicool/thrust,h1arshad/thrust,hemmingway/thrust,Vishwa07/thrust,h1arshad/thrust,levendlee/thrust,lishi0927/thrust,rdmenezes/thrust,bfurtaw/thrust,julianromera/thrust,rdmenezes/thrust,h1arshad/thrust,google-code-export/thrust,levendlee/thrust,google-code-export/thrust,bfurtaw/thrust,h1arshad/thrust,allendaicool/thrust,Vishwa07/thrust,malenie/thrust,Vishwa07/thrust,malenie/thrust,UIKit0/thrust,hemmingway/thrust,bfurtaw/thrust,UIKit0/thrust,julianromera/thrust,allendaicool/thrust,UIKit0/thrust,hemmingway/thrust,hemmingway/thrust,allendaicool/thrust,levendlee/thrust,lishi0927/thrust,malenie/thrust,lishi0927/thrust,julianromera/thrust,lishi0927/thrust,google-code-export/thrust,rdmenezes/thrust,rdmenezes/thrust