[development] Please be careful marking release nodes "Security update"

[Karoly Negyesi]

> Could we add a flag that say "change the use of the DB"?
> If it doesn't, testing/upgrading is just a matter of moving a
> directory and copy the new version in the right place.
> 
> If there is some change at the DB level (schema or code that use the
> DB) a backup would be a more conservative choice.

DB and API changes must happen in a new branch. Any given branch should not contain anything else but bugfixes just like Drupal core.