Remove account system

[emiltin]

Remove everything related to accounts and login/logout.
Favorite locations, which are used in the app, will be stored on the device instead of on the backend.
All account data will be deleted as part of implementing this.

NOTE: This can be developed now in a branhc, but should not be deployed until after a new version of the app active for a while, so locations have been store locally.

[NCdpac]

Update: Branch has been prepared with changes that remove the account system completely from the accessible site. Backend account system is still available in this branch, to ensure compatibility with apps until account system has been removed from these. Please provide feedback if backend account system should also be removed immediately with the branch.

[emiltin]

the branch should complete remove the acocunt system, including db tables that relates to users, favorite locations.

note: we don't deploy this yet. we first need an updated app to be live for a few weeks, so locations are transfered to the users local device

[emiltin]

@NCdpac please create a pull request for the branch