code: function finishedAction(state, action) {
    const new_actions = Object.assign({}, state.actions);
    delete new_actions[action.id];
    return Object.assign({}, state, {actions: new_actions});
  }
docs: Record a WFS action as finished in the state.
  @param {Object} state Current state.
  @param {Object} action Action to handle.
  
  @returns {Object} The new state.