Add note about potential kernel fusion in the CUDA merge implementation
Add note about potential kernel fusion in the CUDA merge implementation

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