Do not let user make project public with private data

[jeffbaumes]

Disallow making a project public unless they first make the data public. It would be fine to have a message (like "Can't make this public. First make the data public."). Better might be a warning with a choice (like "The data for this project is private. Make the data public?" with Ok/Cancel buttons).

[jeffbaumes]

Of course the user could later make the data private again and break the project, but this would at least disallow a cause of unexpected behavior.

[waxlamp]

Is this what's going on in #431?

[jeffbaumes]

I wouldn't think so, since the public projects should point to public data.