Implement device gather with device for_each.
Implement device gather with device for_each.

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