Creating new project should default to public

[abachant]

Would we want to subtly encourage users to make their projects public by making it the default as opposed to how it is now?

Essentially just turn this:

into this:

[petebachant]

I don't know. I think it's kind of nice to start out with a private project. Working in public is scary for people because they think they'll be "scooped". I'd be happy if they get to the point where they're about to submit their paper, and make it public then. We could have a nice easy process for archiving all the files and inserting the DOI into the project's references so they can cite it in the paper.