Integrate with advancedqueue and send entities as new messages to VGWort

Fixed the tests. This is now ready for some review.

Still need to write more tests of the logic inside the EntityQueuer and the queue processing.

This looks all good to me. The testing is great and I can confirm, that the queue stuff works. Since we cannot test against some vgwort endpoint, I would suggest to just merge for now. Actual problems will have to be found out the hard way...

Thank you @daniel.bosen

Automatically closed - issue fixed for 2 weeks with no activity.