feat(wepback): Add app reducer hot reloading

common/app/create-app.jsx

@@ -1,4 +1,5 @@
 import { Observable } from 'rx';
+import createDebugger from 'debug';
 import { compose, createStore, applyMiddleware } from 'redux';
 import { selectLocationState, connectRoutes } from 'redux-first-router';
 import { combineReducers } from 'berkeleys-redux-utils';
@@ -14,6 +15,7 @@ import epics from './epics';
 import { onBeforeChange } from './utils/redux-first-router.js';
 import servicesCreator from '../utils/services-creator';
 
+const debug = createDebugger('fcc:app:createApp');
 // createApp(settings: {
 //   history?: History,
 //   defaultState?: Object|Void,
@@ -84,6 +86,21 @@ export default function createApp({
   const store = createStore(reducer, defaultState, enhancer);
   const location = selectLocationState(store.getState());
 
+  // note(berks): should get stripped in production client by webpack
+  // We need to find a way to hoist to top level in production node env
+  // babel plugin, maybe? After a quick search I couldn't find one
+  if (process.env.NODE_ENV === 'development') {
+    if (module.hot) {
+      module.hot.accept('./reducer.js', () => {
+        debug('hot reloading reducers');
+        store.replaceReducer(combineReducers(
+          require('./reducer.js').default,
+          panesReducer,
+          routesReducer
+        ));
+      });
+    }
+  }
   // ({
   //   redirect,
   //   props,