Guest Accounts

[iaktern]

The MS should be usable without login. So, a person using PROCEED without login is automatically a "Guest" user.

• Add a configuration in the MS Server Settings: "Guest Expiration Time", default = 5 days
• Create an "Expiration Database" which should link the guest accounts and there expiration date
• Guest Account creation: Assign a unique ID for every Guest, create a new Environment, set a Cookie with the unique ID and expiration time to "Guest Expiration Time", add the guest account to the "Expiration Database".
• Renew the cookie (and process artefakt deletion) during every user activity
• Recognize the guest during subsequent visits and show her all her processes if not expired.
• Create a daily batch process functionality (ask @OhKai ) for deleting expired guest accounts and all their artefacts.
• Store all guest processes and artefacts in the Backend like with normal Users
• In the MS, show a banner that the processes and its artefacts are deleted after the expiration time
• During User Registration, transfer all already created process artefacts to the new User Environment

[FelipeTrost]

The last points where implemented in #652