message: Removed unnecessary one-time check
  The buildCurrentUrl is only called once?! Thought it was called when navigating back to start but isn't. Think it was when wasn't doing an initial replace - but the initial replace means don't get the blank url anymore because the first url is # instead of blank now
diff: @@ -10,13 +10,10 @@ import {getHome, getTweet, getTimeline} from './data';
  export default () => {
  const buildCurrentUrl = url => {
  const {state, data} = stateNavigator.parseLink(url);
  - const {previousState} = stateNavigator.stateContext;
  let fluent = stateNavigator.fluent().navigate('home');
  - if (!previousState)
  stateNavigator.historyManager.addHistory(fluent.url, true);
  if (state.key === 'photo') {
  fluent = fluent.navigate('tweet', {id: data.id});
  - if (!previousState)
  stateNavigator.historyManager.addHistory(fluent.url);
  }
  return fluent.navigate(state.key, data).url;
  