In this PR
1. Enable deletion of relation fields in the product and via the api
(migration part was missing in the api)
3. Change wording, only use "deactivate" and "delete" everywhere (and
not a mix of the two + "disable", "erase")
Fixes#5276.
Updates were not triggering a cache version incrementation because they
do not trigger migrations while that is where the caching version logic
was.
We have decided to move the cache incrementation logic to the services.
