On volunteer sign-up page, display details of the need(s) the volunteer is signing up for

Go to /civicrm/vol/#/volunteer/opportunities. Check the box for one or more volunteer opportunities. Click the sign up button.

You're taken to a page where the sign up can be completed. The need ID(s) the volunteer is signing up for are passed via the URL, and the profiles for the projects associated with those needs are displayed to the user.

The purpose of this ticket is to summarize the Needs in the shopping cart (or in the URL at this point) on the same page where the sign-up happens. Like the vol opp search form, I think the relevant information to display is: Project, Beneficiary, Role, and Time. Ideally, the Needs would be grouped by Project.

Ideally, the display will be responsive-friendly.