Add history.listenBeforeUnload, deprecate (un)registerBeforeUnloadHook
Add history.listenBeforeUnload, deprecate (un)registerBeforeUnloadHook

PactCoffee/history,iam4x/history,narr/history,ReactTraining/history,rackt/history,knowbody/history,narr/history,mjackson/history,knowbody/history,jesenko/history,ReactJSTraining/history,knowbody/history,jesenko/history,reactjs/history,iam4x/history,jesenko/history,narr/history,mjackson/history,rackt/history,PactCoffee/history,iam4x/history,ReactJSTraining/history,PactCoffee/history,reactjs/history