add a hidden delete all CBL DBs

[Fujio-Turner]

When showing a demo of the mobile training to many new people , example at a booth in a conference, it be great to start from a clean stale when even needed. Could you add a hidden pull down. So after you logout you can delete all the CBL DBs
True you also have to stop and start SG and delete the CB Bucket.

When showing off N1QL to show all active task by user1 and you see all the older task from a demo 5 minutes ago its confusing to people.