text: export default function(state = null, action) {
  
      switch (action.type) {
          case 'FETCH_DATA_PENDING':
              return 0;
          case 'PARSE_DATA_START':
              return {
                  done: 0,
                  total: action.payload
              };
          case 'PARSE_DATA_STEP':
              return {
                  done: action.payload.done,
                  total: action.payload.total
              };
          case 'FETCH_DATA_FULFILLED':
              return null;
          default:
              return state;
      }
  }
  