- failed validation doesn't prevent save/load,
but the user is now warned about it.
- there is now a warning dialog if fromJSON fails,
rather than the usual silent failure.
- clarified docstrings and errors
- still more notebook/file renames
- configurable untitled names
- copy_from can be full path
- fix running, upload, new-tab behaviors in dashboard
Yay, review!
MinRK