Auto merge of #1160 - emberjs:locks-patch-3, r=locks
Auto merge of #1160 - emberjs:locks-patch-3, r=locks

Update feature-flags.md

boztek/guides,MarkMT/guides,davidpett/guides,HeroicEric/guides,jkarsrud/guides,tleskin/guides,ubuntuvim/guides,vikram7/guides,knownasilya/guides,davidpett/guides,HeroicEric/guides,skaterdav85/guides,tleskin/guides,ubuntuvim/guides,skaterdav85/guides,MarkMT/guides,tleskin/guides,nicobot/guides,vikram7/guides,bmac/guides,knownasilya/guides,nicobot/guides,boztek/guides,knownasilya/guides,skaterdav85/guides,MarkMT/guides,jkarsrud/guides,HeroicEric/guides,boztek/guides,bmac/guides,davidpett/guides,jkarsrud/guides,davidpett/guides,bmac/guides,greyhwndz/guides,greyhwndz/guides,nicobot/guides,ubuntuvim/guides,knownasilya/guides,greyhwndz/guides,ubuntuvim/guides,jkarsrud/guides,MarkMT/guides,vikram7/guides,bmac/guides,skaterdav85/guides