docs(local-storage): update doc to clarify useLocalStorage type restr…

…iction (#92)

Add a tip to hint that value could be an array, plain-object or other types. The feature is not pretty frank in demo.

packages/local-storage/docs/useLocalStorage.md

@@ -11,7 +11,7 @@ order: 2
 
 # useLocalStorage
 
-Retrieve value from `localStorage` by key, also returns a function to update it.
+Retrieve value from `localStorage` by key, also returns a function to update it. Value could be any type which can be handled by `JSON.stringify`.
 
 ```typescript
 function useLocalStorage<T>(key: string, initialValue: T): [T, (value: T) => void]