use account metadata for allowing unsafe deletions

[sampsapenna]

Proposed solution

Current implementation of deletions doesn't allow deleting containers which have objects within them, due to the large risk associated with a destructive operation of this magnitude. It should be useful to allow this on a per-project basis, which would mean allowing unsafe deletes in Openstack Swift account metadata.

DoD (Definition of Done)

The UI has an option to allow deleting containers with contents with the delete button inside a single project.

Testing

Simple verification of correct frontend behavior by hand.