We create them. let's reflect that in the verb.

Only storing the date as that should suffice for normal expiry and is less useful for identifying users by timestamps

preparing for #5664 with some test improvements i ran into this issue

This commit includes a fix and the test improvements. In particular it
adds BrowserIntegrationTest#login - so there is no need to go through the signup procedure everytime you want a user to be logged in.

The changes to the configuration required some non minor changes to the platform and also added some flexibility we don't require yet - and thus some new possibilities for errors.

So instead we still use the allow_..._certs and ..._cert_prefix options.
They basically provide the framework in which service levels can operate.

The service level configuration will not include the cert prefix anymore.
It only states if the service level is rate limited or not.
This avoids conflicts between the two configuration options.

I also removed the anonymous service level entirely.
It was also turning a boolean decision (do we provide anonymous eip or not) into something way more complex. Instead I added the AnonymousServiceLevel class to handle the corner cases for people who are not logged in.

Furthermore i renamed the UnauthenticatedUser to AnonymousUser so it matches the Anonymous Service Level nicely. It's also shorter and more intuitive.

Null Pattern for current_user - use it to get rid of some conditionals

:api/service will return a hash of the current users service level

This is failiing if the user is not logged in. Instead it should return the service description for an anonymous user.

cleaned up all the engine stuff that was never really used.
Afterwards there is not that much left that makes it into the toplevel.