Feature Request: Admin management features

It would be useful for an admin to be able to manage other user data.

As it stands today, an admin can see how many shares a user has created. Anything more would require a password change (which an admin can do) or digging in the database.

Examples of some things I'd think an admin should be able to do -

- Examine what a user's aliases and shares
- Manage their files.

One way to do this would be to allow an admin to impersonate a user in the API (to pass a userid in the request for example)