0.2.0 can upload, activate, deactivate and roll back, but never remove, so a
themes volume only grows. Deferred deliberately from the 0.2.0 cycle.
The shape is already there to copy: refuse deleting the active theme the same
way replacing it is refused, give the refusal a reason an operator reads, and
ratify it as a scenario in test/features/features.
Open question for the spec: whether deleting the theme a rollback would return
to is refused, or allowed with the rollback target cleared.
0.2.0 can upload, activate, deactivate and roll back, but never remove, so a
themes volume only grows. Deferred deliberately from the 0.2.0 cycle.
The shape is already there to copy: refuse deleting the active theme the same
way replacing it is refused, give the refusal a reason an operator reads, and
ratify it as a scenario in test/features/features.
Open question for the spec: whether deleting the theme a rollback would return
to is refused, or allowed with the rollback target cleared.