Gds upgrade add in router

When this is deployed it needs a migration running to sort out the prefixes that it thinks needs to be right for registering with the router. Without this migration being run, things may well explode when you try to publish or create a new artefact.

The router does not exist. Keeping it deactivated/harmless is based on this non-existent var: ENV['QUIRKAFLEEG_ACTIVATE_AN_ROUTER']. 

All the wiring is still in there so when/if you want to switch it on, you just need to run an initial register all the things but after that it'd work \o/

Recommend this is merged in the morning after @Floppy has had a look over it.