Adding React.js, Redux, revamping dashboard

app/assets/javascripts/components/reducers/statuses.jsx

@@ -0,0 +1,17 @@
+import { SET_TIMELINE, ADD_STATUS } from '../actions/statuses';
+import Immutable                    from 'immutable';
+
+const initialState = Immutable.Map();
+
+export default function statuses(state = initialState, action) {
+  switch(action.type) {
+    case SET_TIMELINE:
+      return state.set(action.timeline, Immutable.fromJS(action.statuses));
+    case ADD_STATUS:
+      return state.update(action.timeline, function (list) {
+        list.unshift(Immutable.fromJS(action.status));
+      });
+    default:
+      return state;
+  }
+}