As a user making some of the datasets in my Project Space public, I want to specify what level of access public users have (e.g. commenting, downloading, etc).

Note: After the 2.0 Early Access release, users will have the ability to make their entire Project Space public (i.e. all the things in their space) or particular datasets public. This story is about extending that functionality by allowing users to say what type of access is conferred to public users.

Acceptance criteria tbd