title: 'group' state gets saved in store.default.group instead of store.group
body: <p>I made a reducer called 'group' but when I call the store I see it's saved inside store.default.group. Why isn't it in store.group instead? How come I have a default inside it?</p>
  
  <p>index reducer:</p>
  
  <pre><code>import { combineReducers } from 'redux'
  
  import counter from './counter'
  import group from './groupReducer'
  
  export default combineReducers({
    counter,
    group,
  })
  </code></pre>
  
  <p>Group reducer:</p>
  
  <pre><code>import * as types from '../actions/actionTypes';
  
  const initialState = {
    name: null,
    route: null,
    grade: null,
    coins: 0,
    image: null,
  };
  
  export default function reducer(state = initialState, action = {}) {
    switch (action.type) {
      case types.SET_GROUP_NAME:
        return {
          ...state,
          name: action.name
        };
      case types.SET_GROUP_ROUTE:
        return {
          ...state,
          route: action.route
        };
      case types.ADD_GROUP_COINS:
        return {
          ...state,
          coins: state.count + action.coins
        };
      case types.REMOVE_GROUP_COINS:
        return {
          ...state,
          coins: state.count - action.coins
        };
      case types.SET_GROUP_IMAGE:
        return {
          ...state,
          image: actions.image
        };
      case types.SET_GROUP_grade:
        return {
          ...state,
          grade: action.grade
        };
      default:
        return state;
    }
  }
  </code></pre>
  
  <p>My connect function:</p>
  
  <pre><code>export default connect(store =&gt; ({
      group: store.default.group
    }),
    (dispatch) =&gt; ({
      actions: bindActionCreators(groupActions, dispatch)
    })
  )(StartGame);
  </code></pre>
  
  <p>EDIT:</p>
  
  <p>Creating store:</p>
  
  <pre><code>import React, {Component} from 'react';
  import { createStore, applyMiddleware, combineReducers } from 'redux';
  import { Provider } from 'react-redux';
  import thunk from 'redux-thunk';
  
  import * as reducers from '../reducers';
  import Routing from './Routing';
  
  const createStoreWithMiddleware = applyMiddleware(thunk)(createStore);
  const reducer = combineReducers(reducers);
  const store = createStoreWithMiddleware(reducer);
  
  export default class App extends Component {
    render() {
      return (
        &lt;Provider store={store}&gt;
          &lt;Routing /&gt;
        &lt;/Provider&gt;
      );
    }
  }
  </code></pre>