Fix possible exploit in savedView.

Restrict adding keys into a ds, unless the user owns it.  Also do not add key into public datastream (ds).
Then, use the request.user as secondary authentication when loading savedViews.  This way if a key isn't in the
      graph, but a person still has permissions, it loads properly.
Merge branch 'staging' of github.com:visgence/portcullis into staging