renames top/bottom to first/last, adds a debounced call to updateChildStates to cleanup when scrolling ends
renames top/bottom to first/last, adds a debounced call to updateChildStates to cleanup when scrolling ends

runspired/ember-radar,html-next/vertical-collection,shime/smoke-and-mirrors,aquamme/smoke-and-mirrors,dukex/smoke-and-mirrors,gordonbisnor/smoke-and-mirrors,runspired/smoke-and-mirrors,runspired/ember-radar,shime/smoke-and-mirrors,ssendev/smoke-and-mirrors,igorrKurr/smoke-and-mirrors,ssendev/smoke-and-mirrors,html-next/vertical-collection,runspired/smoke-and-mirrors,aquamme/smoke-and-mirrors,html-next/vertical-collection,gordonbisnor/smoke-and-mirrors,dukex/smoke-and-mirrors,igorrKurr/smoke-and-mirrors