PRINT SCREEN on MBAIR? Is there a way to print screen the MBAir and paste it on a preloaded program like iPhoto and create a jpeg file. With a PC, it has a "Prt Scr" key and then paste it to a photo software. I don't see one on this Air. With my 4S, i can hold the Power and Home Button simultaneously and prints the screen. Any help would be great. Thanks.