title: How to make redux-persist blacklist for nested state?
body: <p>Here is my code for <code>persistConfig</code> and <code>store</code>, I want to add <code>blacklist</code> for <code>tracking</code>, but not for all tracking state, but only for <code>tracking.checkingOut</code>, <code>tracking.checkingIn</code> and <code>tracking.searching</code>, how to do this correctly? I understand that if I want to remove tracking completely, I will need to write <code>blacklist: ['tracking']</code> inside <code>persistConfig</code>, but I'm not sure what to do in case of nested states. </p>
  
  <pre><code>const persistConfig = {
      key: 'root',
      storage: AsyncStorage,
    }
  
  const persistedReducer = persistReducer(persistConfig, reducers)
  
  const createStoreWithMiddleware = applyMiddleware(thunkMiddleware)(createStore);
  
  export const store = createStoreWithMiddleware(persistedReducer);
  
  export const persistor = persistStore(store);
  </code></pre>
  
  <p>if I will add blacklist like this: blacklist: ['tracking.checkingOut', 'tracking.checkingIn', 'tracking.searching'] will it work? or there should be different approach for this?</p>