code: function mergeDefaults(obj, src) {
      var objValue = Immutable.fromJS(obj);
      var srcValue = Immutable.fromJS(src);
  
      return srcValue.mergeDeep(objValue).toJS();
  }
docs: Merge
  @param  {Object|Map} obj
  @param  {Object|Map} src
  @return {Object}