code: function (saga, callback) {
      var sagaId = saga.id || saga;
      this.sagaStore.remove(sagaId, callback);
    }
docs: Use this function to remove the matched saga.
  @param {String}   saga     The id of the saga or the saga itself
  @param {Function} callback The function, that will be called when this action is completed. [optional]
  `function(err){}`