Deleting all the revisions should move the whole document to the recycle bin

Since we can delete just a few revisions from the history, it is also possible to delete all of the revisions. However, doing that will leave the main document in place, having the same version as the last removed one, and the history shows no versions.

We should either:

• prevent deleting the last version
• or moving the document to the recycle bin when there are no more versions left in the history.

I'd say that the latter option is better.