Logout
🚀 Feature Proposal
As a user, I want to have the posibility to log myself out of the app.
Motivation
Useful for changing the user e.g.
Technical Details
On logout: destroy firebase token -> do not receive notifications anymore -> requires Firebase #...
Redirect to Login Screen.
Example
The user "Otto123" wants to log himself/herself out, in order to let his/her friend create a new Akamu account. Thus he/she clicks on "Logout"