Client | save and load the user token

[Shahar Kazaz]

The client needs to save the user token in order to chain it into the HTTP requests.
The token will be saved in the local storage.
When the app starts we need to check if the token in our local storage is still valid or not:

• If it's valid we need to get the active user and update the app state.
• If expired we need to perform the logout operation.