As request is used to request destruction, ignore instances related to only
delivered cleanup deliveries.

All tests have to pass with all possible combinations of code, so virtual
separation is meaningless.

This test will allow to track progress on "securing" API -- that it will
disallow to access objects outside of its scope.

Thanks to this browser will ask for newer version of data all the time,
but server will have a chance to reply with 304 (Not Modified).

Return object of access points.

API date is based on developer time, not document modification time.

Instance API has to be used to update its status.

Also use bobobase_modification_time as fallback.

Also switch to decorator based logic.